DETECTION OF Y-CHROMOSOMAL DNA WITH MARKER CHROMOSOMES IN TURNERS-SYNDROME

Patients with clinical features of Turner's syndrome may have a 45,X/4 6,X + mar or 46,X + mar karyotype. It is estimated that phenotypic fem ales or intersexuals with a Y chromosome and gonadal dysgenesis have a 20% risk of developing gonadoblastoma, so it is crucial to know wheth er Turner's syndrome patients have a Y chromosome. We studied the chro mosomal make-up of four patients with Turner's syndrome using the poly merase chain reaction (PCR). Nine Y-chromosomal loci including four lo ci (PABY, SRY, ZFY, DYS14) on the short arm, one loci (DYZ3) on the ce ntromere, and four loci (DYS132, DYS1, DYZ1, DYZ2) on the long arm wer e amplified to determine the origin of marker chromosomes. Three patie nts were identified as having Y chromosome DNA. Patient 1 contained th e presumed gonadoblastoma locus (DYS132) and a prophylactic gonadectom y was carried out. DNA extracted from dysgenetic gonads did not show Y chromosome DNA A rapid, highly sensitive and isotope-free method for detection of abnormal Y chromosomes in Turner's syndrome patients has been developed. Chromosome in situ hybridization analysis is required to confirm the PCR results, to provide further evidence for molecular organization of these marker chromosomes.