Prenatal diagnosis of the maternal derivative chromosome der(15)t(Y;15)(q12;p13) in a dizygotic twin pregnancy.

Sex chromosome translocations are unique and must be considered separately from translocations between autosomes. Here, we describe the first prenatal case of one twin fetus with an unbalanced translocation between chromosome Y and chromosome 15, presenting a 46,XY,der(15)t(Y;15) karyotype. The other twin had a normal 46,XY karyotype.

Discrepancy of cytogenetic analysis in Western and eastern Taiwan.

Objective: This study aimed at investigating the results of second-trimester amniocyte karyotyping in western and eastern Taiwan, and identifying any regional differences in the prevalence of fetal chromosomal anomalies.

Methods: From 2004 to 2009, pregnant women who underwent amniocentesis in their second trimester at three hospitals in western Taiwan and at four hospitals in eastern Taiwan were included. All the cytogenetic analyses of cultured amniocytes were performed in the cytogenetics laboratory of the Genetic Counseling Center of Hualien Buddhist Tzu Chi General Hospital.