BMPR1B Research Articles

Effect of Bone Morphogenetic Protein Receptor-1B (BMPR-1B) Gene Variant on Litter Size in Akkaraman Sheep Breed

The BMPR-1B gene, a significant fertility gene, has been examined for its relationship with fertility characteristics in various sheep populations globally. This investigation explored the impact of the BMPR-1B gene on litter size within the Akkaraman sheep population residing in the Elâzığ Region. To locate the FecB gene in Akkaraman sheep, 104 milk samples were collected, and genetic material was isolated using the salting out technique. During the 2021–2022 period, no significant correlations were observed between the genetic make-up of Akkaraman sheep and factors including age, mastitis and disease history, milk yield, birthing type, and the number of births (p > 0.05). However, there was a noteworthy relationship identified between the distribution of genetic make-up and live weight, indicating a potential influence of genetics on the live weight of Akkaraman sheep (p < 0.05). In this study, the BMPR-1B gene determined multiple births and it was determined that Akkaraman sheep were monomorphic in terms of this gene. In light of this information, it was concluded that more comprehensive studies should be carried out regarding this gene determining multiple births in the Akkaraman sheep breed.

Acromesomelic Dysplasia With Homozygosity for a Likely Pathogenic BMPR1B Variant: Postaxial Polydactyly as a Novel Clinical Finding.

Acromesomelic chondrodysplasias are a rare subgroup of the clinically and genetically heterogeneous osteochondrodysplasias that are characterised by abnormalities in the limb development and short stature. Here, we report a 2-year-old boy, offspring of consanguineous parents, with acromesomelic dysplasia and postaxial polydactyly in which exome sequencing identified a novel homozygous missense variant in BMPR1B. The patient showed skeletal malformation of both hands and feet that included complex brachydactyly with the thumbs most severely affected, postaxial polydactyly of both hands, shortened toes as well as a bilateral hypoplasia of the fibula. Whole trio exome sequencing was conducted to identify potential genetic variants in the patient. The analysis identified the biallelic variant NM_001203.3:c.821A > G;p.(Gln274Arg) in BMPR1B, a gene encoding bone morphogenetic protein receptor 1B. The skeletal phenotype can be brought in line with the phenotypes of previously reported cases of BMPR1B-associated chondrodysplasias. However, the postaxial polydactyly described here is a novel clinical finding in a BMPR1B-related case; notably, it has previously been reported in other acromesomelic dysplasia cases caused by homozygous pathogenic variants in GDF5-a gene which encodes for growth differentiation factor 5, a high-affinity ligand to BMPR1B.

FecBB mutation enhances follicle stimulating hormone sensitivity of granulosa cells by up-regulating the SMAD1/5–USF1–FSHR signaling pathway

The FecBB mutation, a single-point mutation (c.A746G; p.Q249R) in bone morphogenetic protein receptor type 1 B (BMPR1B), is associated with increased ovulation quotas and litter size in sheep. However, the regulatory mechanism of the FecBB mutation in increased fecundity remains to be elucidated. Therefore, creating an immortal cell model harboring the FecBB mutation would elucidate the regulatory mechanism of this mutation. Here, we report the creation of a human granulosa cell, COV434, model containing a homozygous FecBB mutation through homology-directed repair (HDR) induced by clustered, regularly-interspaced, short palindromic repeats–CRISPR-associated protein 9 along with a single-stranded oligodeoxynucleotide (ssODN) template. We found that the FecBB mutation enhanced the basal SMAD1/5 signaling activity in COV434 cells, leading to increased expression of FSHR, probably through increased formation of the SMAD1/5–SMAD4 complex to bind to the SBE element, which in turn promotes the binding of USF1 to the regulatory element E-box in the promoter of FSHR. Furthermore, the FecBB mutation substantially enhanced estradiol (E2) synthesis in granulosa cells under follicle stimulating hormone (FSH) stimulation, indicating an enhanced sensitivity to FSH, which may promote the growth of more small follicles into mature follicles, leading to increased fecundity. Our study provides novel insights into the possible regulatory mechanisms of FecBB mutations in increased fecundity.

Genetic regulation of ovulation rate and multiple births.

Ovulation rate in many mammalian species is controlled to regulate the numbers of offspring and maximise reproductive success. Pathways that regulate ovulation rate still respond to genetic and environmental factors and show considerable variation within and between species. Genetic segregation, positional cloning, and association studies have discovered numerous mutations and genetic risk factors that contribute to this variation. Notable among the discoveries has been the role of mutations in bone morphogenetic protein 15 (BMP15 ), growth differentiation factor 9 (GDF9 ) and bone morphogenetic protein receptor type 1B (BMPR1B ) from the intra-ovarian signalling pathway contributing to the evidence that signalling from the oocyte is the key driver in follicle regulation rather than circulating gonadotrophin concentrations. Multiple variants in different domains of BMP15 and GDF9 result in partial or complete loss of function of the proteins providing insights into their functional roles and differential regulation contributing to species differences in ovulation rate. Early success encouraged many more studies in prolific strains of sheep, cattle and goats providing a valuable catalogue of genetic variants of large effect increasing ovulation rate and litter size. More recently, genetic association studies are beginning to identify genetic risk factors with smaller effects. Most genes implicated are from pathways with defined roles in regulation of the ovarian function. However, some genomic regions suggest regulation by novel genes. Continuing genetic and related functional studies will add further to our understanding of the detailed regulation of ovulation rate and litter size with implications for health and animal production systems.

The Impact of Novel BMPR1B Mutations on Litter Size in Short-Tailed Gobi Sheep and Larger-Tailed Ujimqin Sheep.

The significant deposition of tail fat in sheep has a profound impact on the economic benefits of animal husbandry. Furthermore, increasing the litter size is a crucial means of enhancing economic benefits. The BMPR1B and T/Brachyury genes are considered major functional genes that could affect sheep litter size and tail bone number, respectively. In this study, we employed direct sequencing to identify specific mutations of the BMPR1B gene in Gobi short tail sheep and carried out genotyping using MassARRAY technology for each variant of both the BMPR1B and T genes. Significant associations were demonstrated between the c.687G>A mutation of BMPR1B and the litter size in both the Gobi short tail sheep and Ujimqin sheep breeds. Meanwhile, the g.30058882_30058873GCAGATTAAAIndel mutation was significantly associated with the litter size in Gobi short tail sheep. These findings may provide valuable genetic markers for expanding sheep litter size. In addition, we also confirmed that the frequency of tail-bone-number-related T alleles was significantly higher in Gobi short tail sheep than in longer-tailed Ujimqin sheep.

Correlation between BMPR1B Gene Polymorphism and some Reproductive Traits in Awassi Sheep

The (BMPR-1B) gene is one of the main genes for ewe fertility. This study was conducted to check the association between BMPR-IB gene polymorphisms and some traits of Awassi. This study was made in Anbar Governorate - (Agricultural Research Department) Al-Dawar. Date of experience collected from 34 ewes at the age of 4-6 years. Next, DNA was extracted and a PCR reaction was performed to amplify blood samples taken from the ewes to confirm the presence of the BMPR1B gene. The sequence was determined using Sanger sequencing technology. The data were then analyzed and compared between sample sequences to determine SNPs, genotype frequencies, allele frequencies, and their association with reproductive and growth traits. The results showed mutations in the heteroplasmy site rs410310346 (T>C) and rs592447725 (G>A). The results indicated that the TC genotype at the mutation site rs410310346 (T>C) was significantly superior (P≤0.05) in ewes whose rates of fertility and body length were higher compared to the CC genotype. The genotypes haven’t got an important effect on the proportion of twins, fertility rate, chest circumference, front height, ewe birth weight, and lamb weight at birth. The relationship of genotype GG and GA at the mutation site rs592447725 (G > A) showed a very significant effect (P≤0.01) on the percentage fertility rate and a noteworthy result (P≤0.05) on body length, height at the front and birth weight of lambs, but there isn’t a big impact. In the percentage of twins, fertility rate, chest circumference, and birth weight of ewes. Therefore, the effect of the BMPR1B gene can be used as a genetic marker to select ewes with good genotypes to improve herd performance.

New Variant Found in the Bone Morphogenetic Protein Receptor 1B Gene in a Neonate With Trisomy 21

New Variant Found in the Bone Morphogenetic Protein Receptor 1B Gene in a Neonate With Trisomy 21

Detection of Booroola Polymorphism of Bone Morphogenetic Protein Receptor 1b and Embrapa Polymorphism of Growth Differentiation Factor 9 in Sheep in Thailand.

This study aimed to investigate the appearance and frequencies of the Booroola polymorphism of the bone morphogenetic protein receptor 1b (BMPR1B) gene (FecB) and the Embrapa polymorphism of the growth differentiation factor 9 (GDF9) gene (FecGE) in sheep in Thailand. A total of 454 crossbred sheep blood samples were collected from four provinces in Thailand during August 2022 to July 2023. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to identify the FecB and FecGE genotypes. The history of ewe birth types was collected from the owners to analyze the association between fecundity (Fec) genotypes and the history of birth types. The genotypic frequencies of FecB for homozygous genotype (B/B), heterozygous genotype (+/B), and wildtype (+/+) were 0.22%, 1.54%, and 98.24%, respectively. Meanwhile, the genotypic frequencies of FecGE for homozygous genotype (E/E), heterozygous genotype (+/E), and wildtype (+/+) were 0.00%, 2.42%, and 97.58%, respectively. Furthermore, three ewes exhibited both FecB and FecGE genotypes. Fisher's exact test revealed that possession of the FecB genotype was associated with multiple births (p < 0.01). Both FecB and FecGE mutations were identified in crossbred sheep in Thailand. Sheep containing FecB allele could be alternative candidates to be selected to improve the prolificacy of crossbred sheep in Thailand.

A repertoire of single nucleotide polymorphisms (SNPs) of major fecundity BMPR1B gene among 75 sheep breeds worldwide

The BMPR1B gene is a major determinant of sheep reproductive capacity. Previous studies revealed that Q249R (FecB) is a profound variant of BMPR1B that influences the ovulation rate and litter size in sheep. However, unlike Q249R locus, the full spectrum of single nucleotide polymorphisms (SNPs) within BMPR1B has not been extensively studied. A systematic screen of SNPs in BMPR1B would facilitate the discovery of novel variants that are associated with litter size. This study aimed to investigate SNPs in the BMPR1B gene via whole genome sequence (WGS) data from 2409 individuals of 75 sheep breeds worldwide. Herein, a total of 9688 variants were screened, among which 15 were coding variants and 8 were novel changes. Specifically, we presented the most comprehensive frequency distribution map of the well-known FecB mutation to date. Besides, among the above-mentioned SNPs, one synonymous mutation (g.30050773C > T) was found to be likely under selection and is potentially associated with fecundity in Duolang sheep. Thus, our study greatly expands the variation repertoire of the ovine BMPR1B gene and provides a valuable resource for exploring causative mutations and genetic markers associated with litter size.

Polymorphisms of the BMPR1B, BMP15 and GDF9 fecundity genes in four Chinese sheep breeds

Abstract. Numerous studies on prolific sheep breeds have shown that the transforming growth factor beta (TGF-β) superfamily members, including bone morphogenetic protein receptor type 1B (BMPR1B), bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9), are the essential regulators of ovulation rate and litter size. In total, 11 known mutations (1 in BMPR1B, 6 in BMP15 and 4 in GDF9) are able to increase the ovulation rate and litter size, respectively. In this study, the genomic DNA was isolated from 512 high-prolificacy sheep (including the Small-tailed Han, Hu and Wadi sheep breeds) and 164 low-prolificacy sheep (Tan sheep), and genotyping of the specific mutations of the three fecundity-related genes was carried out by sequencing. The results showed that the FecB mutation in BMPR1B was detected in all four sheep breeds, and the frequency of B allele was significantly higher in the high-prolificacy breeds than that in the low-prolificacy breed (P&lt;0.001). A novel mutation, c.T755C (named S1), was found in BMP15 from the four sheep breeds. However, known mutations such as FecXI, FecXH, FecXB, FecXG, FecXL and FecXR were not detected in these breeds. Three known loci (G1, G3 and G4) and a new mutation, c.A1515G (named S2), were found in GDF9, and the other three known mutations (FecGH (G8), FecGE and FecTT) were not detected in all four sheep breeds. The genotype distribution at the G1 and G4 loci had significant differences between the low-prolificacy sheep breed and the other three high-prolificacy sheep breeds. There was no difference in the genotype distribution at the G1 and G4 loci between the three high-prolificacy sheep breeds. Haplotype analysis of the four polymorphic loci in GDF9 suggested that H4 (GGAA) was the preponderant haplotype in the three high-prolificacy sheep breeds, but H1 (GGGG) was in the low-prolificacy sheep breed. These results preliminarily showed that the BMPR1B and GDF9 might be major genes influencing the prolificacy of Chinese sheep breeds.

Phenotypic features, transcriptomic signatures and genomic regions associated with body ellipticity in the flatfish Senegalese sole

Body shape is a complex and plastic trait with a high impact on fish performance and commercialization. Shape is particularly relevant in flatfish with highly asymmetric bodies. In this study we investigated the skeleton features, transcriptomic profiles and genomic regions in two Senegalese sole groups from a full-sib family with positive (named as HE) or negative (LE) breeding values for body ellipticity (ELL). Soles from HE group were heavier and displayed more elongated bodies than LE. A skeleton analysis showed that HE had a higher number of vertebrae, longer vertebral bodies and intervertebral spaces and a lower incidence of skeletal fusions than LE. With respect to the gender effect, females showed a higher height of ventral body and some differences in the ratio urostyle to skeleton length than males for similar ELL values. The PCA analysis using 28 dimensionless morphological traits indicated that PC1 and PC2 explained 51.3% of the total variance and they were mainly associated with ELL and gender variation, respectively. Expression analysis using two factors (ELL and gender) revealed a major effect of gender in muscle, pterygiophores and liver with 6764, 6506 and 7559 differentially expressed transcripts (DETs) between sexes, respectively. In brain, only 16 DETs were identified. When HE and LE were compared controlling by gender, we identified the subset of DETs with conserved responses in both sexes or those regulated in a sex-specific manner in each tissue. A comparison across tissues identified 31 ubiquitous transcripts as differentially expressed in at least two of them. Functional analysis showed that liver and pterygiophores had the highest number of enriched gene ontology categories (24 and 14, respectively). Some of these enriched pathways were related to regulation of cell cycle, cell structure and shape, locomotory behavior, immune system, hormonal responses and homeostasis. A BSR-Seq analysis confirmed five significant genomic windows associated with ELL by using the tricube-smoothed G' and Fst statistics. Windows located in linkage groups (LG) 5 and LG14 included the malt1 and vtg3 genes, respectively, that were also detected within the subset of ubiquitous DETs. Moreover, malt1 appeared located very close to the bmpr1b gene within the significance hotspot of LG5 indicating that mediators of the inflammatory responses and BMP signaling pathway could be responsible for the differences found in the skeleton features and body ellipticity.

Determination of the Effect of GDF9, BMP15, BMPR1B Gene Polymorphism, and Environmental Factors for Fecundity by Logistic Regression Analysis in Kangal Akkaraman Sheep

Determination of the Effect of GDF9, BMP15, BMPR1B Gene Polymorphism, and Environmental Factors for Fecundity by Logistic Regression Analysis in Kangal Akkaraman Sheep

Proteomic Analysis Identifies Distinct Protein Patterns for High Ovulation in FecB Mutant Small Tail Han Sheep Granulosa Cells.

The Booroola fecundity (FecB) mutation in the bone morphogenetic protein receptor type 1B (BMPR1B) gene increases ovulation in sheep. However, its effect on follicular maturation is not fully understood. Therefore, we collected granulosa cells (GCs) at a critical stage of follicle maturation from nine wild-type (WW), nine heterozygous FecB mutant (WB), and nine homozygous FecB mutant (BB) Small Tail Han sheep. The GCs of three ewes were selected at random from each genotype and consolidated into a single group, yielding a total of nine groups (three groups per genotype) for proteomic analysis. The tandem mass tag technique was utilized to ascertain the specific proteins linked to multiple ovulation in the various FecB genotypes. Using a general linear model, we identified 199 proteins significantly affected by the FecB mutation with the LIMMA package (p < 0.05). The differential abundance of proteins was enriched in pathways related to cholesterol metabolism, carbohydrate metabolism, amino acid biosynthesis, and glutathione metabolism. These pathways are involved in important processes for GC-regulated 'conservation' of oocyte maturation. Further, the sparse partial least-squares discriminant analysis and the Fuzzy-C-mean clustering method were combined to estimate weights and cluster differential abundance proteins according to ovulation to screen important ovulation-related proteins. Among them, ZP2 and ZP3 were found to be enriched in the cellular component catalog term "egg coat", as well as some apolipoproteins, such as APOA1, APOA2, and APOA4, enriched in several Gene Ontology terms related to cholesterol metabolism and lipoprotein transport. A higher abundance of these essential proteins for oocyte maturation was observed in BB and WB genotypes compared with WW ewes. These proteins had a high weight in the model for discriminating sheep with different FecB genotypes. These findings provide new insight that the FecB mutant in GCs improves nutrient metabolism, leading to better oocyte maturation by altering the abundance of important proteins (ZP2, ZP3, and APOA1) in favor of increased ovulation or better oocyte quality.

Genetic Variation of rs429976637, rs416717560, rs403555643 and rs427046713 in BMPRP1B Gene and its Frequency of Awassi Sheep

Bone protein receptor gene (BMPR1B) is a significant fertility gene found in sheep globally and associated to reproductive and fertility features. This study verified the relationship between the BMPR1B gene’s 893 G A SNP1, SNP2, SNP3, and SNP4 C T 893. 35 Awassi ewe blood samples were acquired from the Agricultural Research Department in Anbar Governorate – Al Dawar, followed by DNA extraction to validate the BMPR1B gene and PCR amplification. The Sanger Sequences technique of single nucleotide polymorphism (SNP) was employed to determine each ewe’s special alleles using the gene primer. Four BMPR1B gene sites had substantially varied genotype and allele frequencies (P < 0.01). The association study indicated that the rs429976637 (G>A) locus had three polymorphisms, GG, GA, and AA, with percentages of 92.16, 7.68, and 0.16%, respectively, and allelic frequencies of G - 0.96 and A-0.04. Polymorphisms differed (P=0.01). rs416717560 (G>A) had three polymorphisms: GG, GA, and AA. The allelic frequency of the G alleles was 0.91, and polymorphism was 82.82, 16.38, and 0.80%. Polymorphism differed by 0.09 (P=0.01). The rs403555643 locus (A>G) has three polymorphisms, AA, AG, and GG, with percentages of 92.14, 7.68, and 0.16%, respectively, and allelic frequencies of A-0.96 and G - 0.04 (P < 0.01). The locus rs427046713 (C>T) had three polymorphisms, CC, CT, and TT, with percentages of 94.09, 5.82, and 0.09%, respectively. The allelic frequency of C alleles was 0.97- and T 0.03--P < 0.01. The allelic frequency of the BMPR1B gene for four loci is considerably greater for genotypes GG, GG, AA, and CC.

A novel variant in BMPR1B causes acromesomelic dysplasia Grebe type in a consanguineous Moroccan family: Expanding the phenotypic and mutational spectrum of acromesomelic dysplasias.

Acromesomelic dysplasia Grebe type (AMD Grebe type) is an autosomal recessive trait characterized by short stature, shortened limbs and malformations of the hands and feet. It is caused by variants in the growth differentiation factor 5 (GDF5) or, in rare cases, its receptor, the bone morphogenetic protein receptor-1B (BMPR1B). Here, we report a novel homozygous BMPR1B variant causing AMD Grebe type in a consanguineous Moroccan family with two affected sibs from BRO Biobank. Remarkably, the affected individuals showed additional features including bilateral simian creases, lumbar hyperlordosis, as well as lower limb length inequality and dislocated hips in one of them, which were never reported previously for AMD Grebe type patients. The identified novel BMPR1B variant (c.1201C>T, p.R401*) is predicted to result in loss of function of the BMPR1B protein either by nonsense-mediated mRNA decay or production of a truncated BMPR1B protein. Thus, these findings expand the phenotypic and mutational spectrum of AMD, and may improve the diagnosis of AMD and enable appropriate genetic counselling to be offered to patients.

Investigation for Mutation in BMPR-1B (FecB) Fecundity Gene in Awassi Sheep

Reproduction related traits in sheep such as ovulation rate and litter size are traits of high economic importance but as these traits are only expressed in one sex and in mature animals, thus inclusion of them in selection strategies is limited. Therefore, studying genes associated with reproductive events provides genotypic data, which is more useful in genetic improvement of sheep in a short period of time. Such reproductive traits in sheep are genetically controlled by genes having both additive and major effects. Booroola is the first gene identified in Booroola Merino sheep in Australia has major effects on ewe’s reproduction and has gained much popularity in sheep breeding for its immense economic value. Booroola or Bone Morphogenetic Protein Receptor -1B (BMPR-1B) gene is in chromosome 6 and FecB allele is the result of a single mutation in this gene where one copy of this allele results in a significant increase in ovulation rate thus outcome as increased lambing per parturition. The Awassi sheep is an indigenous breed of Turkey and identifying major genes for fecundity could greatly improve their breeding program. To identify the FecB gene in Awassi sheep, 88 blood samples were taken, and DNA was extracted by salting out method. After PCR amplification and AvaΠ digestion, the samples were analyzed for FecB mutation and all of 88 samples were found not to carry the mutant allele (FecB).

Single-cell RNA reveals a tumorigenic microenvironment in the interface zone of human breast tumors

BackgroundThe interface zone, area around invasive carcinoma, can be thought of as the actual tissue of the tumor microenvironment with precedent alterations for tumor invasion. However, the heterogeneity and characteristics of the microenvironment in the interface area have not yet been thoroughly explored.MethodsFor in vitro studies, single-cell RNA sequencing (scRNA-seq) was used to characterize the cells from the tumor zone, the normal zone and the interface zone with 5-mm-wide belts between the tumor invasion front and the normal zone. Through scRNA-seq data analysis, we compared the cell types and their transcriptional characteristics in the different zones. Pseudotime, cell–cell communication and pathway analysis were performed to characterize the zone-specific microenvironment. Cell proliferation, wound healing and clone formation experiments explored the function of differentially expressed gene BMPR1B, which were confirmed by tumor models in vivo.ResultsAfter screening, 88,548 high-quality cells were obtained and identified. Regulatory T cells, M2 macrophages, angiogenesis-related mast cells, stem cells with weak DNA repair ability, endothelial cells with angiogenic activity, fibroblasts with collagen synthesis and epithelial cells with proliferative activity form a unique tumorigenic microenvironment in the interface zone. Cell–cell communication analysis revealed that there are special ligand–receptor pairs between different cell types in the interface zone, which protects endothelial cell apoptosis and promotes epithelial cell proliferation and migration, compared to the normal zone. Compared with the normal zone, the highly expressed BMPR1B gene promotes the tumorigenic ability of cancer cells in the interface zone.ConclusionsOur work identified a unique tumorigenic microenvironment of the interface zone and allowed for deeper insights into the tumor microenvironment of breast cancer that will serve as a helpful resource for advancing breast cancer diagnosis and therapy.

CRISPR/Cas mediated disruption of BMPR-1B gene and introduction of FecB mutation into the Caprine embryos using Easi-CRISPR strategy

Bone Morphogenetic Proteins play a significant role in ovarian physiology and contribute to the reproductive fitness of mammals. The BMPR-1B/FecB mutation, a loss of function mutation increases litter size by 1–2 with each number of mutated alleles in sheep. Considering demand-supply gap of the meat industry, and low replacement rate of indigenous caprine species, the conservative BMPR-1B locus can be explored, and FecB mutated goats can be produced. The experiment one produced CRISPR/Cas mediated KO transferable caprine embryos, and experiment two generated caprine embryos with desired FecB mutation using Easi-CRISPR strategy. In the KO experiment, Cas9 and BMPR-1B guide RNA (100:100ng/ul) were electroporated into single stage caprine zygotes at 750V, 10 ms and 1pulse using Neon transfection system. In the second experiment, phosphorothioate (PS) modified single-stranded oligodeoxynucleotide (ssODN) was used as an HDR template along with CRISPR components (100:100ng/ul, ssODN 100ng/ul). The precise time and method of electroporation, RNP format of CRISPR components and PS modified asymmetric ssODN were the factors that affected the production of mosaicism free BMPR-1B edited caprine embryos. The editing efficiency of KO and KI experiments was 68.52 and 63.16% respectively, and successful production of goats with higher mean ovulation rate can be realized with addition of embryo transfer technology to these experiments.

Screening for causative mutations in ovine BMPR1B and BMP15 genes and their homologous fragments in human.

The BMPR1B and BMP15 genes are well known for their considerable associations with prolificacy in sheep. These genes may also affect fertility or prolificacy in other species, including human. This study was conducted to investigate possible causative mutations in BMPR1B and BMP15 genes in human and an indigenous breed of sheep. Blood samples were collected from 83 singleton- and prolific Mehraban ewes and 81 infertile, singleton- and twin-bearing women. A 190-bp fragment, containing the FecB mutation in ovine BMPR1B, a 380-bp fragment in ovine BMP15 gene and their homologous fragments in human were amplified and then investigated by single-stranded conformation polymorphism and DNA sequencing methods. The FecB mutation of BMPR1B (g.159A>G) was detected in the sheep population, but no polymorphic loci were found in the homologous fragment in studied human samples. The studied fragments of BMP15 were monomorphic in both sheep and human samples. A total of nine and 69 point-differences in the studied fragments of BMPR1B and BMP15 genes were detected between the species, respectively. In sheep, the G allele of BMPR1B had a positive effect on litter size (p<0.05), whereby all AG or GG ewes were prolific. The FecB mutation for the first time was detected in Mehraban sheep and therefore could be considered for marker-assisted selection in this breed. The studied fragments of BMPR1B and BMP15 genes are not responsible for reproduction variation in human. More studies on other genes, associated with fertility in human, are necessary in the future.

Steroidogenic enzyme gene expression and testosterone production are developmentally modulated by bone morphogenetic protein receptor-1B in mouse testis.

Bone morphogenetic proteins (BMPs) and receptors (BMPR-1A, BMPR-1B, BMPR-2) have been shown to be vital for female reproduction, while their roles in males are poorly described. Our study was undertaken to specify the function of BMPR-1B in steroidogenic enzyme gene expression, testosterone production and reproductive development in male mice, given that Bmpr1b mRNA is expressed in mouse testis and Bmpr1b knockout results in compromised fertility. Male mice were passively immunized for 6 days with anti-BMPR-1B in the presence or absence of exogenous gonadotrophins. We then measured the effects of anti-BMPR-1B on testicular hydroxysteroid dehydrogenase isoforms (Hsd3b1, Hsd3b6, and Hsd17b3) and aromatase (Cyp19) mRNA expression, testicular and serum testosterone levels, and testis and seminal vesicle weight. In vitro testosterone production in response to anti-BMPR-1B was determined using testicular culture, and Leydig cell culture in the presence or absence of gonadotrophins. In Leydig cell culture the contribution of seminiferous tubules and Leydig cells were examined by preconditioning the media with these testicular constituents. In adult mice, anti-BMPR-1B increased testosterone and Hsd3b1 but decreased Hsd3b6 and Cyp19 mRNA. In adult testicular culture and seminiferous tubule conditioned Leydig cell culture, anti-BMPR-1B reduced testosterone, while in normal and Leydig cell conditioned Leydig cell culture it increased testosterone levels. In pubertal mice, anti-BMPR-1B reduced gonadotrophin stimulated seminal vesicle growth. In conclusion, BMPR-1B has specific developmental functions in the autocrine and paracrine regulation of testicular steroidogenic enzyme gene expression and testosterone production in adults and in the development of seminal vesicles during puberty.