A de novo SOX10 mutation causing severe type 4 Waardenburg syndrome without Hirschsprung disease.

Type 4 Waardenburg syndrome represents a well define entity caused by neural crest derivatives anomalies (melanocytes, intrinsic ganglion cells, central, autonomous and peripheral nervous systems) leading, with variable expressivity, to pigmentary anomalies, deafness, mental retardation, peripheral neuropathy, and Hirschsprung disease. Autosomal dominant mode of inheritance is prevalent when Sox10 gene mutation is identified. We report the natural history of a child who presented with synophrys, vivid blue eye, deafness, bilateral complete semicircular canals agenesis with mental retardation, subtle signs for peripheral neuropathy and lack of Hirschsprung disease. SOX10 gene sequencing identified "de novo" splice site mutation (c.698-2A > C). The present phenotype and the genotype findings underline the wide spectrum of SOX10 gene implication in unusual type 4 Waardenburg syndrome patient.

Two fast methods for detection of Y-microdeletions.

OBJECTIVE: To test two recently available commercial kits: the new Promega Y Chromosome Deletion Detection System 2.0 kit and the Bird-Set kits (Y Chromosome UE and Extension). DESIGN: A comparative technical study. SETTING: Male infertility clinic. PATIENT(S): Twelve various Y chromosome microdeleted patients were included in the present study: two AZFa deleted, two AZFb deleted, four AZFb+c deleted, three AZFc deleted, and one AZF a+b+c deleted. INTERVENTION(S): DNA samples were tested with both the Promega kit and the Bird-Set kits. MAIN OUTCOME MEASURE(S): Electrophoresis and analysis comparison on a bioanalyzer. RESULT(S): Both kits (Promega 2.0 and Bird Y Chromosome UE) confirmed the 12 Y deletions. Both kits (Bird Extension and Promega 2.0) were able to determine the length of the 12 microdeletions with various differences. The new Promega 2.0 kit was considerably improved, with the addition of two sequenced tag sites (STS) in AZFa (sY86 and sY84) and the deletion of some (sY239 and sY153) but not all supernumerary inadequate STS. CONCLUSION(S): The two new commercially available kits use two different protocols to detect Y chromosome microdeletions. The Promega kit is a one-step diagnostic test. The Bird diagnostic test uses a two-step protocol. Both kits offer relevant methods such as standardization and ready-to-use mixes. However, both kits need further evaluation under routine conditions using nontested DNA samples.