[Infrequent X chromosome abnormality and X-linked syndromic deafness].

Objective: To make clear the relationship between the X chromosome abnormality and sydromic deafness through genetic analysis of a pedigree with X-linked syndromic deafness.

Methods: The chromosome number and structure of the family members were analyzed by the standard and high resolution banding with Giemsa, and fluorescent in situ hybridization. The allelic number of the DNA segment in X chromosome was studied with genetic markers.

[Molecular cloning for an alternatively splicing cDNA of human PKNOX1 gene and it's expression analysis].

Down's syndrome (DS) is the most common chromosomal abnormality in live born infants. The cloning and characterization of genes on HC21 are necessary steps for the understanding of the molecular basis of Down's syndrome. To search for new Down's syndrome related genes, we have used bioinformatics analysis and rapid amplification of cDNA ends to identify an alternatively splicing cDNA of human PKNOX1 in Down's syndrome critical region on the long arm of human chromosome 21.