SUN-034 Combined CNV, Haplotyping and Whole Exome Sequencing Implicates Inherited Novel SRY Mutations Not Account for Familial 46,XY Sex Reversal

Abstract

SRY is one of the important genes involved in the process of human sex determination. The disturbed sex determination caused by SRY mutation accounts for 10-15% cases with complete gonadal dysplasia (CGD), also known as 46, XY sex reversal. Recently, three distal enhancers are disclosed in the upstream of SOX9 gene. In an inherited 46, XY sex reversal pedigree with 5 patients, p.Arg76Leu mutation of SRY and p.G212S mutation of NR5A1were identified from the proband who present with primary amenorrhea and lack of puberty development. The missense mutation of NR5A1was found to be derived from the mother. Interestingly, the paternal inherited p.Arg76Leu mutation of SRY was revealed from other 2 CGD patients, as well as from apparent normal male family members with fertility. P.Arg76Leu variation was found have no effect to the transcriptional activity of target gene SOX9, neither alteration of the nuclear translocation of SRY. Whole exome sequencing also found SRY mutation, FGF10 mutation, GJB4 gene mutation, etc. with no segregation in the family, which suggested SNVs are not main cause of the disease in this pedigree. By copy number variation and SNP haplotype analysis, SOX9 gene far upstream deletion of 68kb was disclosed from the 3 patients in this family, containing one of the enhancers of SOX9. Real-time PCR confirmed that the heterozygous deletion of the region result in loss of SR-XY, but not eSR-B and eALDI. Therefore, single nucleotide variation (SNV) of SRY and NR5A1 are not main causes of severe phenotype of CGD, the enhancers of SOX9 should be investigated carefully in such patients.