Better Understanding Of Genotypes Research Articles

Evolutionary Profile of Mayaro Virus in the Americas: An Update into Genome Variability

The Mayaro virus (MAYV) is an arbovirus with emerging potential, though with a limited understanding of its epidemiology and evolution due to the lack of studies and surveillance. Here, we investigated 71 MAYV genome sequences from the Americas available at GenBank and characterized the phylogenetic relationship among virus strains. A phylogenetic analysis showed that sequences were grouped according to the genotypes L, D, and N. Genotype D sequences were closely related to sequences collected in adjacent years and from their respective countries, suggesting that isolates may have originated from circulating lineages. The coalescent analysis demonstrated similar results, indicating the continuous circulation of the virus between countries as well. An unidentified sequence from the USA was grouped with genotype D, suggesting the insertion of this genotype in the country. Furthermore, the recombination analysis detected homologous and three heterologous hybrids which presented an insertion into the nsP3 protein. Amino acid substitutions among sequences indicated selective pressure sites, suggesting viral adaptability. This also impacted the binding affinity between the E1–E2 protein complex and the Mxra8 receptor, associated with MAYV entry into human cells. These results provide information for a better understanding of genotypes circulating in the Americas.

Systematic Approach Revealed SERPING1 Splicing-Affecting Variants to be Highly Represented in the Czech National HAE Cohort

Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) is a rare and life-threatening condition characterized by recurrent localized edema. We conducted a systematic screening of SERPING1 defects in a cohort of 207 Czech patients from 85 families with C1-INH-HAE. Our workflow involved a combined strategy of sequencing extended to UTR and deep intronic regions, advanced in silico prediction tools, and mRNA-based functional assays. This approach allowed us to detect a causal variant in all families except one and to identify a total of 56 different variants, including 5 novel variants that are likely to be causal. We further investigated the functional impact of two splicing variants, namely c.550 + 3A > C and c.686-7C > G using minigene assays and RT-PCR mRNA analysis. Notably, our cohort showed a considerably higher proportion of detected splicing variants compared to other central European populations and the LOVD database. Moreover, our findings revealed a significant association between HAE type 1 missense variants and a delayed HAE onset when compared to null variants. We also observed a significant correlation between the presence of the SERPING1 variant c.-21 T > C in the trans position to causal variants and the frequency of attacks per year, disease onset, as well as Clinical severity score. Overall, our study provides new insights into the genetic landscape of C1-INH-HAE in the Czech population, including the identification of novel variants and a better understanding of genotype–phenotype correlations. Our findings also highlight the importance of comprehensive screening strategies and functional analyses in improving the C1-INH-HAE diagnosis and management.

Cytogenomic characterization of a de novo 4q34.1 deletion in a girl with mild dysmorphic features and a coagulation disorder

Background4q deletion syndrome is a rare chromosomal disorder that mostly arises de novo. The syndrome is characterized by craniofacial dysmorphism, digital abnormalities, skeletal alterations, heart malformations, developmental delay, growth retardation, Pierre Robin sequence, autistic spectrum and attention deficit-hyperactivity disorder, although not every patient shows the same features. Array comparative genomic hybridization (aCGH) use improves the detection of tiny chromosomal deletions and allows for a better understanding of genotype–phenotype correlations in affected patients. We report the case of a 6-year-old female patient showing mild dysmorphic features, mild mental disabilities and a coagulation disorder as a consequence of a de novo del(4)(q34.1) characterized by aCGH.Case presentation A 6-year-old female patient exhibited special craniofacial features, such as backward-rotated ears, upslanted palpebral fissures, broad nasal bridges, anteverted nares, broad nasal alae, smooth philtrums, smooth nasolabial folds, thin lips, horizontal labial commissures, and retrognathia. In the oral cavity, maxillary deformation, a high arched palate, agenesis of both mandibular canines and fusion of two mandibular incisors were observed. She also displayed bilateral implantation of the proximal thumbs, widely spaced nipples, dorsal kyphosis, hyperlordosis, and clitoral hypertrophy. In addition, the patient presented with coagulopathy, psychomotor delay, attention deficit-hyperactivity disorder, and mild mental disability. A chromosomal study showed the karyotype 46,XX,del(4)(q34.1), while an aCGH analysis revealed an 18.9 Mb deletion of a chromosome 4q subtelomeric region spanning 93 known genes.ConclusionThe clinical manifestations of this patient were similar to those reported in other individuals with 4q deletion syndrome. Although most of the patients with a 4q34 terminal deletion share similarities, variations in phenotype are also common. In general, clinical effects of chromosomal deletion syndromes depend on the length of the deleted chromosomal segment and, consequently, on the number of lost genes; however, in all of these syndromes, there is no simple correlation between the phenotype and the chromosomal region involved, particularly in cases of 4q deletion.

Novel mutations in the CYBB gene causing X-linked chronic granulomatous disease: a case report of 2 patients

Introduction: Chronic granulomatous disease (CGD) is an inherited primary immunodeficiency caused by mutations in the NADPH complex characterized by recurrent infections, inflammation and autoimmunity. While autosomal recessive forms exist, X-linked CGD makes up the majority of cases, which is caused by mutations in the CYBB gene. Patients are at high risk for infections with catalase positive bacteria and fungi. The prognosis has improved significantly with improvements in disease detection and management, including prophylactic antibiotic and antifungal therapy. Hematopoietic stem cell transplantation (HSCT) is a curative option for patients with a suitable donor. Aim: To report the clinical presentation, immune features and genetic mutations in 2 patients with novel mutations in the CYBB gene causing X-linked CGD who underwent HSCT. Results: Case 1: Patient 1 is a 14-year-old patient who initially presented with disseminated aspergillosis at the age of 3. He was noted to have an abnormal neutrophil oxidative burst index (NOBI) and genetic testing revealed a mutation in the CYBB gene (c.883_87dupGTGGT) consistent with CGD. He successfully underwent HSCT at age 4. At age 10 he developed a primary intracranial rhabdomyosarcoma in the posterior cranial fossa. Case 2: Patient 2 is a 4-year-old male who was worked up for CGD after developing a perianal abscess at 1 month of age followed by Moraxella bacteremia at 2 months of age. He had 2 abnormal NOBIs and genetic testing identified a novel mutation in the CYBB gene that was thought to explain his phenotype (c.941delA). He underwent an HSCT (10/10 HLA matched unrelated donor). Both patients have had normalization of their NOBI post-transplant and remain free of significant infections. Discussion: We report the clinical presentation, immune features and genetic mutations in 2 patients with novel mutations in the CYBB gene causing X-linked CGD. Identifying pathogenic mutations causing CGD is important for a better understanding of genotype–phenotype associations and disease course in this patient population. Statement of novelty: We describe 2 pediatric patients diagnosed with X-linked chronic granulomatous disease due to novel mutations in the CYBB gene.

Breaking the code of antibiotic resistance.

This month's Genome Watch highlights how a better understanding of genotype–phenotype correlation may lead to the design of new diagnostic tests for antimicrobial resistance in clinical settings. This month's Genome Watch highlights how a better understanding of genotype–phenotype correlation may lead to the design of new diagnostic tests for antimicrobial resistance in clinical settings.

Identification of differential co-expressed gene networks in early rheumatoid arthritis achieving sustained drug-free remission after treatment with a tocilizumab-based or methotrexate-based strategy

BackgroundMethotrexate is endorsed to be used as first-line treatment in rheumatoid arthritis (RA). However, a large proportion of patients need additional treatment with a biological disease-modifying anti-rheumatic drug (DMARD) to adequately suppress their disease activity. A better understanding of genotypes could help to distinguish between patients with different pathogenic mechanisms. The aim of this study was therefore to identify networks of genes within DMARD-naive early RA patients associated with achieving sustained drug-free remission (sDFR) after initiating tocilizumab plus methotrexate, tocilizumab, or methotrexate therapy.MethodsSamples were used from 60 patients from the U-Act-Early study who received tocilizumab plus methotrexate, tocilizumab, or methotrexate therapy, and who achieved sDFR (≥3 months in drug-free remission until the end of the study, n = 37) after therapy was tapered and subsequently stopped, or who were not able to discontinue the therapy as controls (n = 23). Whole blood samples were collected and ribonucleic acid (RNA) was isolated from positive cluster of differentiation 4 (CD4+) and CD14+ cells and analysed using high-throughput sequencing. Weighted gene co-expression network analyses were performed to identify clusters (i.e. modules) of differently expressed genes associated with achieving sDFR and which were subsequently used for pathway analyses.ResultsNetwork analyses within CD4+ cells identified two significant modules in the tocilizumab plus methotrexate arm and four modules in the tocilizumab and methotrexate arms, respectively (p ≤ 0.039). Important pathways in the module best correlating with achieving sDFR were in the tocilizumab plus methotrexate arm related to processes involved with transcription and translation; in the tocilizumab arm, pathways were related to migration of white blood cells and G-protein coupled receptors, and in the methotrexate arm pathways were involved with the response to a bacterial or biotic (i.e. biological material)-related stimulus. No relevant networks could be identified in the sequenced CD14+ cells.ConclusionsWithin networks of co-expressed genes, several pathways were found related to achieving sDFR after initiating therapy with tocilizumab, methotrexate, or the combination. Between the three strategy arms, we identified different networks of predisposing genes which indicates that specific gene expression profiles, depending on the treatment strategy chosen, are associated with a higher chance of achieving sDFR.Trial registrationClinicaltrials.gov, NCT01034137. Registered on 16 December 2009.

ADAPTABILITY AND STABILITY STUDIES IN SUGAR CANE VARIETY

The present study aimed to select the most productive clones of sugar cane that constitute the final phase of evaluation of clones. This crop has socioeconomic importance, for the production of ethanol as a renewable source of energy and less polluting than petroleum-based fuels. In this context, to release of new varieties can be one factor of greatest expression for the development of the sector. Twenty-four clones were evaluated in each mill, five of which were considered as standard and the other 19, as genotypes with potential for recommendation. The trait tons of pol per hectare (TPH) was assessed. Reduction for TPH was observed between cuts, with drop of was around 31.61% from the first to the third cut. Although differences were detected among the methodologies used, all of them contributed to better understanding of genotype x environment interaction, and are effective in recommending responsive genotypes.

Genome Resequencing Reveals Single Nucleotide Polymorphism and Repeat Regions in Giardia lamblia Indian Isolate

Giardia lamblia (syn. Giardia duodenalis and Giardia intestinalis) is a major human infecting intestinal parasite. It is a frequent cause of endemic and epidemic diarrhea. G. lamblia is divided into eight genotypes (A-H) which infect a wide range of mammals and humans, but human infections are caused by Genotypes A and B only. Giardia lamblia strains are speculated to undergo zoonotic transmission and also considerable genetic variation has been identified. To unambiguously determine the genotype of the Indian isolate, we sequenced the genome to high depth coverage and compared the assemblies with the nearly completed WB and DH genome and draft genome of Genotypes E (P15; pig isolate) and B (GS and GS-B; human isolate). Our results identified the Indian isolate to be very closely related to isolate WB and ~97.71% of the sequencing reads aligned to the isolate WBC6 genome. This gave a list of SNPs, InDels and repeat motifs specific to the Indian isolate with the majority of the genome being conserved. This work will layout a framework for the future studies. This study provides an opportunity to develop targeted and genome-wide genetic marker for better understanding of genotypes of Giardia lamblia prevalent in the developing world.

Strategy for grouping wheat genotypes according to environmental responses in multi-location trials

A better understanding of genotype x environment interactions (GEIs) can improve the selection and recommendation of wheat genotypes that are widely adapted and stable in different environments. The objective of this study was to evaluate a strategy to perform a joint analysis in wheat yield trials with genotypes classified according to their interactions with the environment. Measurements of the adaptability and stability estimates were used in the proposed strategy. We analyzed grain yield data from 367 wheat genotypes in 348 yield trials classified into 58 groups. In each group, 25 genotypes at different numbers of locations were evaluated using data from 2010, 2011 and 2012. Joint analysis of variance was performed for each group to determine the genotype contribution to the GEI. The genotypes were grouped into two classes: genotypes that interacted with the environment and genotypes with no interaction with the environment. An additional joint analysis of variance was performed for each class. Grouping genotypes into different classes provided valuable information concerning the dynamics of the GEI, which could enable plant breeders to maximize the efficiency of selection and offer recommendations for stable and widely adapted genotypes. The highest selective accuracy for the genotype effects was obtained for the joint analysis when the GEI was insignificant. The joint analysis of trials for wheat genotypes that interacted with the environment presented the highest selective accuracy for the GEI effect and a reduced selective accuracy for the genotype effect.

Correlation Among Genotype, Phenotype, and Histology in Neuronal Ceroid Lipofuscinoses: An Individual Patient Data Meta-Analysis

BackgroundNeuronal ceroid lipofuscinoses (NCL) are heterogeneous neurodegenerative disorders. A better understanding of genotype–phenotype–histology correlation is expected to improve patient care and enhance understanding for phenotypic variability. This meta-analysis studies the correlation of NCL genotypes with clinical phenotypes, ages of onset, and pathologic findings. MethodsA structured MEDLINE search was performed using search strings incorporating relevant Medical Subject Headings (MeSH) terms. Studies of NCL patients with genetic, clinical, and histologic data were included. Individual patient data were extracted. Chi-square statistic was used to test the genotype differences in clinical phenotypes and histology. The distribution of age(s) of onset as a function of genotype was explored. Pairwise comparisons were performed with robust analysis of variance. ResultsSixty-eight studies including a total of 440 individuals with NCL were analyzed. Genetic testing was performed on 395 patients, and a pathologic mutation was identified in 372 of 395 of them. A significant clustering of genotypes into juvenile-onset (only CLN3) and infantile-onset (all others) phenotypes was observed (P < 0.0001). However, the CLN6 genotype showed a bimodal onset and included 14 of 17 subjects with the adult-onset phenotype. The estimated age of onset was respectively lower for subjects with CLN1 mutation (3.01 years, 95% confidence interval [CI] = 2.54 to 3.49) and higher for those with CLN6 mutation (16.33 years, 95% CI = 15.68 to 16.98), compared with other genotypes (P < 0.05 for pairwise comparisons). There was a significant (P < 0.0001) clustering of genotype observed according to the sampled tissue types and electron microscopic findings. ConclusionsNCL genotypes significantly differ in terms of ages of onset and clinical phenotypes. There is a distinct segregation of genotypes and electron microscopic findings and high-yield tissue types for pathologic study. This information can possibly facilitate testing and diagnosis in resource-limited settings.

Selection for ‘environmental fit’ from existing domesticated species

The selection of farm animals through breeding for human benefit has a very long history. In more recent times the practice of animal breeding has become highly sophisticated and the speed of change in 'production traits' such as rate of growth and milk yield has correspondingly increased dramatically. This narrow focus on production traits led to a number of well-documented examples of 'unfavourable' correlated responses such as negative fertility and health issues in high-yielding dairy cattle, with concerns that animal breeding is inherently antagonistic to animal welfare. In this paper the authors explore some of the questions surrounding breeding and welfare and, specifically, how to conceptualise and improve the 'fit' between the selected animal and the environment, or system, in which the animal is reared and managed. The authors conclude that there is a need for a better understanding of genotype x environment effects on health and welfare traits in order to inform the development of breeding programmes that lead to improved environmental fit in animals. They also see the need for the development of valid traits for assessing health and welfare, greater consideration of early life effects that can also potentially affect environmental fit and a need to consider the impacts of climate change on breeding programmes.

Targeted Sequencing of 179 Genes Associated with Hereditary Retinal Dystrophies and 10 Candidate Genes Identifies Novel and Known Mutations in Patients with Various Retinal Diseases

Hereditary retinal dystrophies (HRDs) are a group of monogenic diseases characterized by an irreversible loss of photoreceptors. HRDs exhibit significant genetic and clinical heterogeneities challenging traditional techniques for determining disease-causal mutations. This study aims to develop an efficient molecular diagnostic platform for HRDs, and to determine the genetic basis for 25 randomly collected Chinese families with a variety of HRDs. We designed a high throughput sequence capture microarray targeting 179 genes associated with HRDs and 10 candidate genes. We combined sequence capture with next-generation sequencing (NGS) to screen for mutations in the cohort of Chinese families. Variants detected by NGS were filtered, validated, and prioritized by pathogenicity analysis. Genotypes and phenotypes were correlated. We identified four recurrent single mutations, two compound mutations, and eight novel putative causative mutations, including five putative pathogenic alleles (e.g., premature stop codons and frame shifts) and three novel missense variants that are very likely pathogenic. These findings provided specific genetic diagnoses in 14 of 25 families (56%). Among these, identification of a mutation in VCAN in a family with a complicated phenotype helped to finalize the clinical diagnosis as Wagner syndrome. In another five families, 11 potential novel pathogenic variants were identified. A substantial number of potential new genes and new mutations associated with HRDs remain to be discovered. Identification of the novel HRDs-causing mutations in our study not only provides a better understanding of genotype-phenotype relationships in these diseases, but also demonstrates that the approach described herein is an effective method for large scale mutation detection among diverse and complicated HRDs cases.

GENOTYPE BY ENVIRONMENT INTERACTION AND PHENOTYPIC STABILITY OF YIELD AND QUALITY IN BROCCOLI (Barassica oleracea VAR. ITALICA).

Better understanding of genotype and environment interaction will help to optimize yield and quality of crops. The objective of this study was to partition the phenotypic variance of yield and quality traits in broccoli into component sources associated with genotype, environment and genotype by environment interaction. In addition, compare the patterns of stability across environments. Three broccoli genotypes have been evaluated in three different growing seasons for yield and both nitrate and vitamin C content. The results revealed a phenotypic variation in all studied traits among broccoli genotypes. A greater proportion of the phenotypic variation was associated with differences among environments. Analysis of variance uncovered a significant effect of genotypes for yield and chemical quality traits which indicates the existence of a high degree of genetic variability in the tested genotypes. Genotype by environment interaction was significant for yield and chemical quality traits indicating that these traits are modified to different levels by the environments where they grown and emphasis on the need for testing genotypes in multiple environments to obtain reliable results. The stability analysis revealed that different degrees of stability are existed among genotypes for yield and chemical quality.

Understanding and utilization of genotype-by-environment interaction in maize breeding

Due to the interaction and noise in the experiments, yield trails for studying varieties are carried out in numerous locations and in the course of several years. Data of such trials have three principle tasks: to evaluate precisely and to predict the yield on the basis of limited experimental data; to determine stability and explain variability in the response of genotypes across locations; and to be a good guide for the selection of the best genotype for sowing under new agroecological conditions. The yield prediction without the inclusion of the interaction with the environments is incomplete and imprecise. Therefore, a great deal of breeding and agronomic studies are devoted to observing of the interaction via multilocation trials with replicates with the aim to use the interaction to obtain the maximum yield in any environment. Fifteen maize hybrids were analyzed in 24 environments. As the interaction participates in the total sum of squares with 6%, and genotypes with 2%, the interaction deserves observations more detailed than the classical analysis of variance (ANOVA) provides it. With a view to observe the interaction effect in detail in order to prove better understanding of genotypes, environments and their interactions AMMI (Additive Main Effect and Multiplicative Interaction) and the cluster analysis were applied. The partition of the interaction into the principal components by the PCA analysis (Principal Components Analysis) revealed a part of systematic variations in the interaction. These variations are attributed to the length of the growing season in genotypes and to the precipitation sum during the growing season in environments. Results of grouping by the cluster analysis are in high accordance with grouping observed in the biplot of the AMMI1 model.

Frontiers in the Management of Retinoblastoma

To provide an overview of the current clinical management of retinoblastoma by discussing the trends in the categorization, treatment, and recent advances in molecular diagnostics as well as therapy for retinoblastoma. Literature review and commentary. Selected articles from the medical literature and the authors' clinical and research experience were reviewed critically. Retinoblastoma has evolved from a deadly childhood cancer to a largely curable cancer within the past 40 years. Current treatment strategies aim to salvage the eye and provide the best visual outcome possible. Using the international classification system to stratify intraocular retinoblastoma into treatment groups, the multicenter Children's Oncology Group treatment protocols use 2- to 3-drug chemoreduction with focal consolidative therapy for most categories of disease. Furthermore, collaborative efforts are being directed toward a better understanding of genotype-phenotype relationships in retinoblastoma that will be useful in the multidisciplinary management of this disease. Molecular targeting therapy is emerging as a potential strategy to individualize therapy. Finally, improvements in local drug delivery methods and vehicles are providing solutions for the problem of systemic toxicity from existing chemotherapy regimens. The management of retinoblastoma has become a prototype for other ophthalmic diseases and systemic cancers in which genetic information and molecular targets are being used to design more elegant treatment strategies.

Enhancing the mineral and vitamin content of wheat and maize through plant breeding

More than half of the world's population suffers micronutrient undernourishment. The main sources of vitamins and minerals (iron, zinc, and vitamin A) for low-income rural and urban populations are staple foods of plant origin that often contain low levels or low bioavailability of these micronutrients. Biofortification aims to develop micronutrient-enhanced crop varieties through conventional plant breeding. HarvestPlus, the CGIAR's biofortification initiative, seeks to breed and disseminate crop varieties with enhanced micronutrient content that can improve the nutrition of the “hard to reach” (by fortification or supplementation programmes) rural and urban poor in targeted countries/regions. In attempting to enhance micronutrient levels in maize and wheat through conventional plant breeding, it is important to identify genetic resources with high levels of the targeted micronutrients, to consider the heritability of the targeted traits, to explore the availability of high throughput screening tools and to gain a better understanding of genotype by environment interactions. Biofortified maize and wheat varieties must have the trait combinations which encourage adoption such as high yield potential, disease resistance, and consumer acceptability. When defining breeding strategies and targeting micronutrient levels, researchers need to consider the desired micronutrient increases, food intake and retention and bioavailability as they relate to food processing, anti-nutritional factors and promoters. Finally, ex ante studies are required to quantify the burden of micronutrient deficiency and the potential of biofortification to achieve a significant improvement in human micronutrient status in the deficient target population in order to determine whether a biofortification program is cost-effective.

Genotypic effects of fertilization on seedling sweetgum biomass allocation, N uptake, and N use efficiency.

Screening and selecting tree genotypes that are responsive to N additions and that have high nutrient use efficiencies can provide better genetic material for short-rotation plantation establishment. A pot experiment was conducted to test the hypotheses that (1) sweetgum (Liquidambar styraciflua L.) families have different patterns in biomass production and allocation, N uptake, and N use efficiency (NUE), because of their differences in growth strategies, and (2) sweetgum families that are more responsive to N additions will also have greater nutrient use efficiencies. Seedlings from two half-sib families (F10022 and F10023) that were known to have contrasting responses to fertility and other stress treatments were used for an experiment with two levels of N (0 vs. 100 kg N/ha equivalent) and two levels of P (0 vs. 50 kg P/ha equivalent) in a split-plot design. Sweetgum seedlings responded to N and P treatments rapidly, with increases in both size and biomass production, and those responses were greater with F10023 than with F10022. Growth response to N application was particularly strong. N and P application increased the proportional allocation of biomass to leaves. Under increased N supply, P application increased foliar N concentration and content, as well as total N uptake by the seedlings. However, NUE was decreased by N addition and was higher in F10023 than in F10022 when P was not limiting. A better understanding of genotype by fertility interactions is important in selecting genotypes for specific site conditions and for optimizing nutrient use in forestry production.

A note on stokes-adams disease treated with ephedrin

Neuronal ceroid lipofuscinoses (NCL) are heterogeneous neurodegenerative disorders. A better understanding of genotype–phenotype–histology correlation is expected to improve patient care and enhance understanding for phenotypic variability. This meta-analysis studies the correlation of NCL genotypes with clinical phenotypes, ages of onset, and pathologic findings.A structured MEDLINE search was performed using search strings incorporating relevant Medical Subject Headings (MeSH) terms. Studies of NCL patients with genetic, clinical, and histologic data were included. Individual patient data were extracted. Chi-square statistic was used to test the genotype differences in clinical phenotypes and histology. The distribution of age(s) of onset as a function of genotype was explored. Pairwise comparisons were performed with robust analysis of variance.Sixty-eight studies including a total of 440 individuals with NCL were analyzed. Genetic testing was performed on 395 patients, and a pathologic mutation was identified in 372 of 395 of them. A significant clustering of genotypes into juvenile-onset (only CLN3) and infantile-onset (all others) phenotypes was observed (P < 0.0001). However, the CLN6 genotype showed a bimodal onset and included 14 of 17 subjects with the adult-onset phenotype. The estimated age of onset was respectively lower for subjects with CLN1 mutation (3.01 years, 95% confidence interval [CI] = 2.54 to 3.49) and higher for those with CLN6 mutation (16.33 years, 95% CI = 15.68 to 16.98), compared with other genotypes (P < 0.05 for pairwise comparisons). There was a significant (P < 0.0001) clustering of genotype observed according to the sampled tissue types and electron microscopic findings.NCL genotypes significantly differ in terms of ages of onset and clinical phenotypes. There is a distinct segregation of genotypes and electron microscopic findings and high-yield tissue types for pathologic study. This information can possibly facilitate testing and diagnosis in resource-limited settings.