Microsatellite Alleles Research Articles

Targeted long-read sequencing of the Ewing sarcoma 6p25.1 susceptibility locus identifies germline-somatic interactions with EWSR1-FLI1 binding

Ewing sarcoma (EwS) is a rare bone and soft tissue malignancy driven by chromosomal translocations encoding chimeric transcription factors, such as EWSR1-FLI1, that bind GGAA motifs forming novel enhancers that alter nearby expression. We propose that germline microsatellite variation at the 6p25.1 EwS susceptibility locus could impact downstream gene expression and EwS biology. We performed targeted long-read sequencing of EwS blood DNA to characterize variation and genomic features important for EWSR1-FLI1 binding. We identified 50 microsatellite alleles at 6p25.1 and observed that EwS-affected individuals had longer alleles (>135bp) with more GGAA repeats. The 6p25.1 GGAA microsatellite showed chromatin features of an EWSR1-FLI1 enhancer and regulated expression of RREB1, a transcription factor associated with RAS/MAPK signaling. RREB1 knockdown reduced proliferation and clonogenic potential and reduced expression of cell cycle and DNA replication genes. Our integrative analysis at 6p25.1 details increased binding of longer GGAA microsatellite alleles with acquired EWSR-FLI1 to promote Ewing sarcomagenesis by RREB1-mediated proliferation.

Male’s influence on the primary sex ratio bias in Ryukyu drywood termite

Selfish genetic elements (SGEs) increase their transmission efficiency relative to the rest of the individual genome, which is often deleterious to individual fitness. Theoretical studies have suggested that intragenomic conflict over the sex ratio distortion between SGEs and the rest of the genome should lead to the evolution of sex-determining systems. However, in insects, there are relatively few studies other than those on Dipterans, which makes it difficult to understand the role of SGEs in the evolution of insect sex determination. This is partially due to the difficulties in observing SGEs under field conditions. The effect of SGEs is often masked by the counter-evolution of the resistance genes. Interpopulation cross-breeding experiments are effective to detect the SGEs and their resistance genes. If these populations have different SGEs and resistance genes, cross-breeding experiments reveal their existence by collapsing the evolutionary antagonistic state. The Ryukyu drywood termites Neotermes sugioi, distributed in the Ryukyu Islands, show male-biased sex ratios in pseudergates, nymphs, alates and soldiers both in Okinawa and Ishigaki Islands, but different degrees of bias have been reported between the islands. Male-specific microsatellite alleles have been reported in this species, which allowed us to identify the sex of the eggs and young larvae. In this study, we used the microsatellite locus with male-specific alleles to investigate the primary sex ratio of field colonies on Okinawa and Ishigaki islands and the sex ratio of offspring obtained through cross-breeding experiments between the islands. The primary sex ratios of field colonies were male-biased in Okinawa but not in Ishigaki. Cross-breeding experiments showed that Okinawa males tend to have a male-biased sex ratio in their offspring, but Ishigaki males do not. This result is consistent with the hypothesis that the male bias in this species is caused by SGEs, even though termites are phylogenetically distant from Diptera. Accumulation of knowledge on genetic conflicts in a wide range of taxa might be an important step toward elucidating the mechanisms of diversification of sex determination systems in insects.

Rice performance prediction to deficit irrigation using microsatellite alleles and artificial intelligence

Rice germplasm investigated as completely randomized design under flooding and deficit irrigation conditions. The results of the association analysis indicated that RM29, RM63, and RM53 could be used for rice breeding programs to improve yields under deficit irrigation. The highest accuracy of rice performance prediction was 98.36 for the RFA (RFA) for panicle length, flag leaf length, and width, and the number of primary branches, after that, the MLP algorithm had better prediction power than other algorithms. When a genotypes code was considered as a criterion to classify the genotypes under the drought stress at the reproductive stage, the random forest algorithm (RFA) was the best algorithm based on the predictive accuracy (67.93), kappa value (0.514) and root mean square error (0.293). Based on the artificial intelligence methods, the RFA presented the best results to predict the response of genotypes to deficit irrigation using the microsatellite molecular data.

Differences and changes: an evaluation of the genetic diversity of Arabian mares from Polish state studs born between 1996 and 2013

Abstract The goal of our study was to estimate genetic diversity of Arabian horses from Polish state studs which could have changed due to the extensive use of foreign sires in Polish breeding after 1989. The analysis focused on 1,388 Arabian mares born from 1996 to 2013 in the Białka, Janów Podlaski and Michałów studs. Basic parameters of pedigree, mitochondrial DNA and microsatellite analyses were considered in the study. In the pedigree analysis, changes in the gene pool over the years were noted through the considerable increase of contribution of new founders’ genes and the considerable decrease of inbreeding level. The microsatellite analysis confirmed progressive changes in the gene pool but, contrary to expectations, only three new microsatellite alleles were detected, and a decreased level of heterozygosity was observed. In turn, mtDNA analysis showed a stable genetic situation in the studs throughout the period analysed. The results of the analyses present a diverse picture of the population, which is clearly divided into the three subpopulations of Białka, Janów Podlaski and Michałów, although the pictures presented differed depending on the analytical methods used. Genetic differences among the studs should be considered a positive feature of the Polish population. In order to preserve the present level of population genetic diversity, changes in breeding policy are needed that aim to stop the loss of genes of the historical ancestors of Polish Arabian horses.

Two Microsatellite Types Within NAD6 Gene Help to Distinguish Populations and Infer the Migratory Route of the Invasive Fall Armyworm, Spodoptera frugiperda, (Lepidoptera, Noctuidae) in China

Spodoptera frugiperda is a major agricultural pest that has invaded China since January 2019. Given that most of the individuals present in China carried the diagnostic rice-strain mtDNA (COI-RS), there was no efficient method to distinguish populations of S. frugiperda. In this study, we identified and characterized two variant microsatellite alleles in the mitochondrial NAD6 gene of S. frugiperda retrieved from the National Center for Biotechnology Center GenBank. We then sequenced partial NAD6 genes containing the microsatellite region and the diagnostic COI barcoding gene (used to distinguish the corn-strain and the rice-strain) of 429 invasive S. frugiperda individuals that were collected from the main infested regions in China during 2019-2020. Our data indicates that two kinds of interrupted repeat sequences, (ATA)4T(ATA)3 and (ATA)5T(ATA)3, exist in the microsatellite region which we defined as the deletion type (NAD6-D), and the insertion type (NAD6-I) based on the repeat units' differentiation, respectively. The presence of these two microsatellite types in the mtDNA genome of S. frugiperda was further confirmed with the sequencing results in 429 samples. Moreover, NAD6-I and NAD6-D types were both present in individuals with COI-RS, while only NAD6-D type was detected in the COI-CS individuals. Interestingly, the two microsatellite types suggested a possible geographic distribution: the western migratory route (Yunan and Chongqing) was comprised exclusively of NAD6-I type, while both NAD6-I and NAD6-D types were identified in the predicted eastern migration trajectories (Hainan, Guangxi, Shandong, etc.). These results suggested that NAD6-D and NAD6-I types may be useful in distinguishing between populations, analyzing the evolutionary mechanism of mtDNA microsatellite polymorphism, inferring the migratory route of S. frugiperda in China, and developing precise and integrated control strategies for S. frugiperda.

A comparative study of population genetic structure reveals patterns consistent with selection at functional microsatellites in common sunflower.

Microsatellites, also known as short tandem repeats (STRs), have long been considered non-functional, neutrally evolving regions of the genome. Recent findings suggest that they can function as drivers of rapid adaptive evolution. Previous work on the common sunflower identified 479 transcribed microsatellites where allele length significantly correlates with gene expression (eSTRs) in a stepwise manner. Here, a population genetic approach is used to test whether eSTR allele length variation is under selection. Genotypic variation among and within populations at 13 eSTRs was compared with that at 19 anonymous microsatellites in 672 individuals from 17 natural populations of sunflower from across a cline running from Saskatchewan to Oklahoma (distance of approximately 1600km). Expected heterozygosity, allelic richness, and allelic diversity were significantly lower at eSTRs, a pattern consistent with higher relative rates of purifying selection. Further, an analysis of variation in microsatellite allele lengths (lnRV), and heterozygosities (lnRH), indicate recent selective sweeps at the eSTRs. Mean microsatellite allele lengths at four eSTRs within populations are significantly correlated with latitude consistent with the predictions of the tuning-knob model which predicts stepwise relationships between microsatellite allele length and phenotypes. This finding suggests that shorter or longer alleles at eSTRs may be favored in climatic extremes. Collectively, our results imply that eSTRs are likely under selection and that they may be playing a role in facilitating local adaptation across a well-defined cline in the common sunflower.

Large microsatellite shifts in wild boar after the Fukushima accident

Although nuclear power plant accidents have raised concerns about the genetic consequences of radiation exposure, no studies have successfully compared the DNA of wild animals before and after the accident in the same area around a nuclear power plant. Here, we investigated 12 microsatellites of Japanese wild boar in the Fukushima prefecture before and after the Fukushima Daiichi nuclear accident. A population structure analysis of the microsatellites revealed that wild boar of the 4 prefectures of North Kanto were divided into 5 populations before the nuclear accident. Yet, wild boar sampled after the nuclear accident did not belong to any of these 5 populations. The reason for this result was related to significant changes in the composition of microsatellites after the nuclear accident; on average, 90% of post-accident microsatellite alleles were newly emergent in Fukushima prefecture. In samples obtained before the nuclear accident, each microsatellite had either even or odd-length alleles. Yet, in samples obtained after the nuclear accident, most microsatellites had alleles of both even and odd lengths. Moreover, we examined haplotypes and their frequencies in the mitochondrial DNA control region, and found no significant differences before and after the nuclear accident in both Fukushima and Tochigi prefectures, and no haplotypes were distributed only in distant areas suggesting an influx of wild boar after the nuclear accident. This research suggested that the change in microsatellites was a result of microsatellite instability rather than a result of the migration of wild boar from other areas. This research provides important insights into the effects of a nuclear accident on mammals.

Population genetic analysis of the Humboldt’s flying squirrel using high-throughput sequencing

Abstract The San Bernardino flying squirrel (Glaucomys oregonensis californicus) is thought to be the southernmost population of the Humboldt’s flying squirrel (G. oregonensis) and is restricted to the San Bernardino and San Jacinto Mountains in California. However, recent surveys indicate they have been extirpated from the latter locality. In this study, we characterized the intraspecific genetic structure and diversity of G. oregonensis. We amplified and sequenced at least 300 bp of the mitochondrial cytochrome-b gene and 11 nuclear microsatellites to provide baseline genetic data for this species and subspecies, investigate G. oregonensis genetic structure with a focus on the subspecies distributed in California, and finally evaluate the genetic diversity within G. o. californicus. Population and phylogenetic analyses were performed on a total of 147 samples (tissue, hair, and museum specimen) using the Illumina high-throughput sequencing (HTS) platform, thereby bioinformatically coding microsatellite alleles using established pipelines. Our results indicate reduced genetic diversity in G. o. californicus and highlight genetic distinctiveness of the San Jacinto population. In addition, the differences in genetic diversity between the mitochondrial and nuclear markers suggest sex-biased dispersal and historic separation of the species in multiple refugia followed by more recent gene flow among subpopulations in northern California. This study contributes valuable information toward understanding the genetic variation within G. oregonensis, provides information for future conservation decisions for G. o. californicus, and has novel implications for HTS genotyping-by-sequencing.

Hierarchical Clustering on Principal Components of Microsatellite Frequency Allele Data from Indonesian Buffaloes

Buffalo is a livestock that is used for meat, milk, draught animals, and religious ceremonies in Indonesia. Buffalo genetic information has not been obtained optimally for the development of buffalo breeding programs. Allele frequency is essential information to determine the genetic diversity of a population. This study investigates the use of one of the multivariate analyzes, hierarchical clustering on principal component (HCPC). The data used were microsatellite allele frequency data of 199 swamp buffaloes and 12 river buffaloes in 8 population (7 populations swamp buffalo and 1 population of river buffalo). Furthermore, the data is processed using factoextra and FactoMineR package in R 4.0.0. The results found that the ILSTS61 and ILSTS17 loci could be used as genetic markers to determine the genetic relationship of Indonesian buffalo. From the study, it is concluded that the HCPC method with allele frequency data can be used to analyze genetic relationships in Indonesian buffalo. The PC (Principle Component) value can describe which loci determines the genetic relationship.
 HIGHLIGHTS
 
 Allele frequency data can be used to determine genetic relationships among population
 Principle component value can determine which the loci is influential in determining a genetic relationship
 Hierarchical Clustering on Principal Components can be used to analyze genetic relationships
 
 GRAPHICAL ABSTRACT

Estimation of Zagorsky carps genetic variability using microsatellite analysis

Six microsatellite dinucleotide loci were used to study the genetic variability in three generations of Zagorsky carp. All investigated loci are polymorphic with number of alleles from 4 to 9 per locus. The part of heterozygotes at microsatellite alleles in this breeding group was high, on the average more than 87%. Genetic variability of Zagorsky carp last selective generations has been revealed to be kept high, but it stay lower than that of Moscow Scaly and Moscow Mirror carps (intrabreed types of Parsky breed). Sixth and seventh generations showed somewhat less genetic variability than fifth generation did, in this connection further control of its level is desirable. The loss of 2 alleles from two microsatellite loci, MFW1 and MFW9, was found at sampling of Zagorsky carp seventh generation; these alleles occurred in both preceding generations. 18% of Zagorsky carps had only one of two amplification products (additional) at MFW31 locus, whereas the other carp groups had both products or hadn’t additional product in rare samples. No specific alleles for genetic marking of this breeding group have been found at six microsatellite loci. Allele sizes at all these loci in Zagorsky carp group and in other examined carp groups lay in the same length ranges.

A continent-wide high genetic load in African buffalo revealed by clines in the frequency of deleterious alleles, genetic hitchhiking and linkage disequilibrium.

A high genetic load can negatively affect population viability and increase susceptibility to diseases and other environmental stressors. Prior microsatellite studies of two African buffalo (Syncerus caffer) populations in South Africa indicated substantial genome-wide genetic load due to high-frequency occurrence of deleterious alleles. The occurrence of these alleles, which negatively affect male body condition and bovine tuberculosis resistance, throughout most of the buffalo’s range were evaluated in this study. Using available microsatellite data (2–17 microsatellite loci) for 1676 animals from 34 localities (from 25°S to 5°N), we uncovered continent-wide frequency clines of microsatellite alleles associated with the aforementioned male traits. Frequencies decreased over a south-to-north latitude range (average per-locus Pearson r = -0.22). The frequency clines coincided with a multilocus-heterozygosity cline (adjusted R2 = 0.84), showing up to a 16% decrease in southern Africa compared to East Africa. Furthermore, continent-wide linkage disequilibrium (LD) at five linked locus pairs was detected, characterized by a high fraction of positive interlocus associations (0.66, 95% CI: 0.53, 0.77) between male-deleterious-trait-associated alleles. Our findings suggest continent-wide and genome-wide selection of male-deleterious alleles driven by an earlier observed sex-chromosomal meiotic drive system, resulting in frequency clines, reduced heterozygosity due to hitchhiking effects and extensive LD due to male-deleterious alleles co-occurring in haplotypes. The selection pressures involved must be high to prevent destruction of allele-frequency clines and haplotypes by LD decay. Since most buffalo populations are stable, these results indicate that natural mammal populations, depending on their genetic background, can withstand a high genetic load.

Formation of Potential Heterotic Groups of Oat Using Variation at Microsatellite Loci.

An evaluation of polymorphism at the microsatellite loci was applied in distinguishing 85 oat (Avena sativa L.) genotypes selected from the collection of genetic resources. The set of genotypes included oats with white, yellow, and brown seeds as well as a subgroup of naked oat (Avena sativa var. nuda Koern). Variation at these loci was used to form potential heterotic groups potentially used in the oat breeding program. Seven from 20 analyzed microsatellite loci revealed polymorphism. Altogether, 35 microsatellite alleles were detected (2–10 per locus). Polymorphic patterns completely differentiated all genotypes within the subgroups of white, brown, and naked oats, respectively. Only within the greatest subgroup of yellow genotypes, four pairs of genotypes remained unseparated. Genetic differentiation between the oat subgroups allowed the formation of seven potential heterotic groups using the STRUCTURE analysis. The overall value of the fixation index (Fst) suggested a high genetic differentiation between the subgroups and validated a heterotic grouping. This approach can be implemented as a simple predictor of heterosis in parental crosses prior to extensive field testing or development and implementation of more accurate genomic selection.

Evaluating the Diversity of Ecotypes of Red Clover (Trifolium pratense L.) from Northwestern Spain by Phenotypic Traits and Microsatellites

For more than 50 years, the CIAM-AGACAL (Agricultural Research Centre of Mabegondo, Xunta de Galicia, A Coruña, Spain) has been carrying out the important task of conserving the phytogenetic resources of ecotypes and natural populations of grassland species from northwestern Spain. The CIAM-AGACAL’s germplasm bank has 57 populations of red clover (Trifolium pratense Lam.), one of the most cultivated forage legumes in the world. The goal of the present study was to evaluate the diversity among cultivars and natural clover populations at morphological and molecular level. Twelve polymorphic SSR loci revealed 241 microsatellite alleles with an average of 20.08 alleles per locus. Two main groups were detected by the Structure software, one of them including local populations and the second clustering cultivars and related populations. Intra-specific variability was found among cultivars and natural populations. A moderate genetic differentiation of Spanish red clover cultivars was observed (Fst = 0.08) between the two main clusters. Finally, a certain relationship between phenotypic and genotypic variation was detected.

Genetic Characterization of Indigenous Duck of North-East Region using Microsatellite Markers

Background: Duck farming plays a significant role, next to chicken in the socio-economic uplift men of the rural farmers of North-East India. Pati duck is the most common duck breed in the Brahmaputra valley of Assam and the other common variety reared in North-East India is Chara-Chambeli, however it originatein Kerala. Genetic characterization plays a significant role for formulation of breeding strategies for improvement of any breed. Microsatellites are codominant in nature and are highly polymorphic. High level of allelic variation, co-dominant mode of inheritance and potential for automated analysis make them an excellent tool for genotyping, mapping and genetic characterization. Pati duck is the most common duck breed in the Brahmaputra valley of Assam and the other common variety reared in North-East India is Chara-Chambeli however its origin in Kerela. Therefore, the present investigation was carried out to characterize these two duck breeds using microsatellite markers to evaluate the genetic diversity in these two duck population. Methods: For the present study, Blood sample were collected from 50 Patiducks and 50 Chara-Chambeli ducks from different parts of North-East India. Assessment of genetic characterization of duck breeds of north-east region were carried out using 16 microsatellite markers and population genetics analysis were done by POPGENE software. Result: In the present study, all the studied loci were highly polymorphic. Analysis generated a total of 41 microsatellite alleles. The number of observed alleles (Na) with an overall mean of 1.93±0.258. However, the effective number of alleles (Ne) with a mean of 1.6933±0.2712. The Shannon’s information index was found to a mean value of 0.5685±0.1693. The overall means for observed (HO) and expected (He) heterozygosities were 0.2889±0.2477 and 0.5289±0.0853, respectively. The chi-square (χ2) test for Hardy-Weinberg equilibrium revealed that all the loci are in within Hardy-Weinberg equilibrium.

High Genetic Diversity but Absence of Population Structure in Local Chickens of Sri Lanka Inferred by Microsatellite Markers.

Local chicken populations belonging to five villages in two geographically separated provinces of Sri Lanka were analyzed using 20 microsatellite markers to determine the genetic diversity of local chickens. Population genetic parameters were estimated separately for five populations based on geographic locations and for eight populations based on phenotypes, such as naked neck, long legged, crested or crown, frizzle feathered, Giriraj, commercial layer, crossbreds, and non-descript chicken. The analysis revealed that there was a high genetic diversity among local chickens with high number of unique alleles, mean number of alleles per locus (MNA), and total number of alleles per locus per population. A total of 185 microsatellite alleles were detected in 192 samples, indicating a high allelic diversity. The MNA ranged from 8.10 (non-descript village chicken) to 3.50 (Giriraj) among phenotypes and from 7.30 (Tabbowa) to 6.50 (Labunoruwa) among village populations. In phenotypic groups, positive inbreeding coefficient (FIS) values indicated the existence of population substructure with evidence of inbreeding. In commercial layers, a high expected heterozygosity He = 0.640 ± 0.042) and a negative FIS were observed. The positive FIS and high He estimates observed in village populations were due to the heterogeneity of samples, owing to free mating facilitated by communal feeding patterns. Highly admixed nature of phenotypes was explained as a result of rearing many phenotypes by households (58%) and interactions of chickens among neighboring households (53%). A weak substructure was evident due to the mating system, which disregarded the phenotypes. Based on genetic distances, crown chickens had the highest distance to other phenotypes, while the highest similarity was observed between non-descript village chickens and naked neck birds. The finding confirms the genetic wealth conserved within the populations as a result of the breeding system commonly practiced by chicken owners. Thus, the existing local chicken populations should be considered as a harbor of gene pool, which can be readily utilized in developing locally adapted and improved chicken breeds in the future.

Genotype data not consistent with clonal transmission of sea turtle fibropapillomatosis or goldfish schwannoma

Recent discoveries of transmissible cancers in multiple bivalve species suggest that direct transmission of cancer cells within species may be more common than previously thought, particularly in aquatic environments. Fibropapillomatosis occurs with high prevalence in green sea turtles ( Chelonia mydas) and the geographic range of disease has increased since fibropapillomatosis was first reported in this species. Widespread incidence of schwannomas, benign tumours of Schwann cell origin, reported in aquarium-bred goldfish (Carassius auratus), suggest an infectious aetiology. We investigated the hypothesis that cancers in these species arise by clonal transmission of cancer cells. Through analysis of polymorphic microsatellite alleles, we demonstrate concordance of host and tumour genotypes in diseased animals. These results imply that the tumours examined arose from independent oncogenic transformation of host tissue and were not clonally transmitted. Further, failure to experimentally transmit goldfish schwannoma via water exposure or inoculation suggest that this disease is unlikely to have an infectious aetiology.

Genotype data not consistent with clonal transmission of sea turtle fibropapillomatosis or goldfish schwannoma.

Recent discoveries of transmissible cancers in multiple bivalve species suggest that direct transmission of cancer cells within species may be more common than previously thought, particularly in aquatic environments. Fibropapillomatosis occurs with high prevalence in green sea turtles ( Chelonia mydas) and the geographic range of disease has increased since fibropapillomatosis was first reported in this species. Widespread incidence of schwannomas, benign tumours of Schwann cell origin, reported in aquarium-bred goldfish (Carassius auratus), suggest an infectious aetiology. We investigated the hypothesis that cancers in these species arise by clonal transmission of cancer cells. Through analysis of polymorphic microsatellite alleles, we demonstrate concordance of host and tumour genotypes in diseased animals. These results imply that the tumours examined arose from independent oncogenic transformation of host tissue and were not clonally transmitted. Further, failure to experimentally transmit goldfish schwannoma via water exposure or inoculation suggest that this disease is unlikely to have an infectious aetiology.

First reports of Phytophthora ramorum clonal lineages NA1 and EU1 causing Sudden Oak Death on tanoaks in Del Norte County, California.

A year of forest health surveys has led to the first detection of Phytophthora ramorum in Del Norte County followed by the first wildland detection of the EU1 clonal lineage (Grunwald et al. 2009) of this pathogen in California. In July 2019, leaves were sampled from two tanoaks (Notholithocarpus densiflorus) and 16 California bay laurels (Umbellularia californica) in Jedediah Smith State Park in Del Norte County, the northernmost coastal County of California. Leaves displayed lesions normally associated with Sudden Oak Death (SOD) caused by P. ramorum and were discovered during the citizen science-based survey known as SOD Blitz (Meentemeyer et al. 2015). Samples were surface sterilized using 75% Ethanol and plated on PARPH-V8 agar (Jeffers and Martin 1986). After plating, DNA was extracted and amplified using two P. ramorum-specific assays (Hayden et al. 2006, Kroon et al. 2004). Leaves from two tanoaks exhibiting twig die-back had typical SOD lesions along the midvein, gave positive PCR results and yielded cultures with colony morphology, sporangia and chlamydospores typical of the NA1 lineage of P. ramorum originally isolated in California from tanoaks and coast live oaks (Quercus agrifolia) (Rizzo et al. 2002). The ITS locus and a portion of the Cox-1 locus were sequenced from DNA extracts of each culture using primers DC6-ITS4 (Bonants et al. 2004) and COXF4N-COXR4N (Kroon et al. 2004), respectively. ITS sequences (GB MN540639-40) were typical of P. ramorum and Cox-1 sequences (GB MN540142-3) perfectly matched the Cox-1 sequence of the NA1 lineage (GB DQ832718) (Kroon et al. 2004). Microsatellite alleles were generated as described in Croucher et al. (2013) for the two Del Norte cultures and for eight P. ramorum cultures, representative of the four main multilocus genotypes (MLGs) present in California, namely c1 (Santa Cruz/Commercial Nurseries), c3 (San Francisco Bay Area), c2 (Monterey County), and c4 (Humboldt County) (Croucher et al. 2013). The two Del Norte MLGs were identical to one another and most similar to MLG c1, with a single repeat difference at a single locus. SSR results suggest the inoculum source may not be from Humboldt County, neighboring to the South, but from a yet unidentified outbreak, possibly associated with ornamental plants. Jedediah Smith State Park was surveyed for 12 months following the initial detection, however the pathogen has yet to be re-isolated in that location. In July 2020, SOD symptomatic leaves from two tanoak trees exhibiting twig cankers were collected 8 Km north of Jedediah Smith State Park, where three additional tanoak trees displayed rapidly browned dead canopies consistent with late stage SOD. Leaves were processed as above. Colonies from these samples produced chlamydospores and sporangia typical of P. ramorum on PARPH-V8 agar, but displayed a growth rate faster than that of NA1 genotypes and were characterized by aerial hyphae, overall resembling the morphology of EU1 lineage colonies (Brasier 2003). The EU1 lineage was confirmed by the perfect match of the sequence of a portion of the Cox-1 gene (GB MW349116-7) with the Cox-1 sequence of EU1 genotypes (GB EU124926). The EU1 clonal lineage has been previously isolated from tanoaks in Oregon forests, approximately 55 Km to the North (Grünwald et al. 2016), but this is the first report for California wildlands and will require containment and government regulations. It is unknown whether the EU1 strains in Del Norte County originated from Oregon forests or elsewhere.

Determination of haplotype variation and relationship between desirable agronomic traits and microsatellite alleles on chromosomes 4B and 7D in bread wheat

Determination of haplotype variation and relationship between desirable agronomic traits and microsatellite alleles on chromosomes 4B and 7D in bread wheat

Microsatellites to reveal genetic diversity and to distinguish four mangoes of Tegal District, Central Java, Indonesia

Abstract. Hidayat A, Rahayu ES, Abdullah M, Retnoningsih A. 2021. Microsatellites to reveal genetic diversity and to distinguish four mangoes of Tegal District, Central Java, Indonesia. Biodiversitas 22: 3467-3473. The Wirasangka mango is Tegal District’s flora of identity, which requires recognition, and its existence deserves to be preserved. However, based on the morphology of the fruit, most of the people of Tegal still have difficulty distinguishing the wirasangka mango from other mangoes. Molecular markers are needed to ascertain the differences between these mango varieties. Microsatellite DNA is a repeating DNA of stable DNA markers with high repeatability and polymorphism. This study analyzes the level of genetic diversity and microsatellite alleles that can differentiate four mangoes from Tegal District, Central Java, Indonesia, i.e. wirasangka, tengkueh, golek, and okyong. Eleven accessions of six locations in Tegal District were analyzed using ten microsatellite loci. The microsatellite amplification result was separated using electrophoresis in 6% polyacrylamide gel and then visualized with silver dye. A total of 35 microsatellite alleles were found measuring 100-1000 bp, ranging from 1-7 alleles for each locus. The average polymorphism information content (PIC) of 0.54 indicates that genetic diversity is relatively high and informative. Therefore, the microsatellite alleles can be used to differentiate mango varieties. The specific allele characteristic of wirasangka mango accession is locus AJ63516, with an allele size of 600-700bp.