[Nonsyndromic hereditary deafness genes research progress and related databases].

Deafness is the most prevalent sensory system impairment of human, and 70% of genetic deafness belongs to nonsyndromic hearing impairment. The total number of genes involved in nonsyndromic hereditary deafness has been estimated to above 100. So far, approximate 80 loci have been mapped to human chromosome, and 23 genes have been identified.

[Detection of fetal SRY gene in maternal plasma by real-time fluorescence quantitative PCR].

Objective: To isolate fetal DNA from maternal plasma and examine its fetal origin.

Methods: Fetal DNA in maternal plasma was isolated from 150 samples in the first trimester and mid-trimester of pregnancy, respectively. Real-time fluorescence quantitative polymerase chain reaction PCR (FQ-PCR) was used to determine sex-determining region Y (SRY) gene on Y chromosome.