Heterozygous deletion at the SOX10 gene locus in two patients from a Chinese family with Waardenburg syndrome type II.

OBJECTIVES: Waardenburg syndrome (WS) is a rare disease characterized by sensorineural deafness and pigment disturbance. To date, almost 100 mutations have been reported, but few reports on cases with SOX10 gene deletion. The inheritance pattern of SOX10 gene deletion is still unclear. Our objective was to identify the genetic causes of Waardenburg syndrome type II in a two-generation Chinese family. METHODS: Clinical evaluations were conducted in both of the patients. Microarray analysis and multiplex ligation-dependent probe amplification (MLPA) were performed to identify disease-related copy number variants (CNVs). DNA sequencing of the SOX10, MITF and SNAI2 genes was performed to identify the pathogenic mutation responsible for WS2. RESULTS: A 280kb heterozygous deletion at the 22q13.1 chromosome region (including SOX10) was detected in both of the patients. No mutation was found in the patients, unaffected family members and 30 unrelated healthy controls. CONCLUSIONS: This report is the first to describe SOX10 heterozygous deletions in Chinese WS2 patients. Our result conform the thesis that heterozygous deletions at SOX10 is an important pathogenicity for WS, and present as autosomal dominant inheritance. Nevertheless, heterozygous deletion of the SOX10 gene would be worth investigating to understand their functions and contributions to neurologic phenotypes.

Haplotype frequency and mutation of 17 Y-STR loci in Han population in Guangdong Province / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the polymorphisms of 17 Y-STR loci in Han population in Guangdong Province and explore its application in forensic medicine.</p><p><b>METHOD</b>Seventeen Y-STR loci (DYS19, DYS385a/b, DYS635, DYS389I, DYS389II,DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, Y-GATA-H4) were analyzed using Y filer™ kit in 1000 unrelated individuals and 1000 DNA-confirmed father-son pairs. All mutations were confirmed by DNA sequence analysis.</p><p><b>RESULTS</b>No shared haplotypes were observed among the 1000 unrelated male individuals, and the gene diversity of 17 Y-STR loci ranged from 0.4285 (DYS391) to 0.9654 (DYS385a/b). The samples yielded an overall haplotype diversity of 1.000. A total of 17000 meiotic events were investigated in 1000 father-son pairs with DNA-confirmed biological paternity and 46 differences were observed between the fathers and sons. The average mutation rate was 0.0027 (95%CI, 0.0020-0.0036) per locus.</p><p><b>CONCLUSION</b>The 17 Y-STR loci included in Y-filer have high genetic polymorphisms in South China Han population and have good prospect for application in forensic medicine.</p>