Refining quantitative fluorescent polymerase chain reaction for prenatal detection of X chromosomal anomalies in the major Southeast Asian populations.

Introduction: This study aimed to refine the current quantitative fluorescent polymerase chain reaction (QF-PCR) screen to detect X chromosome anomalies for prenatal diagnosis in the major Southeast-Asian populations.

Methods: 100 amniotic fluid samples from Chinese, Malay and Indian origins were subjected to QF-PCR using the X chromosome markers, HPRT, X22 and AMXY, along with the autosomal marker D21S1411.

Results: Out of the 100 samples tested by markers X22 and HPRT, eight samples were homozygous for both markers, of which seven were resolved by comparison with the autosomal marker D21S1411.

Conclusion: 99 percent of samples could be tested for X chromosome copy numbers, increasing the stringency for detection of X chromosome anomalies by QF-PCR. All results were confirmed by cytogenetics.