Prenatal diagnosis of haemophilia A in China

To develop a one-tube fluorescent multiplexed polymerase chain reaction (PCR) method to perform prenatal diagnosis of haemophilia A (HA).

Peripheral blood samples were collected from 220 women and from members of five families with proven HA. One-tube fluorescent PCR and capillary electrophoresis were performed to investigate four short tandem repeats (STRs) in intron 1, 13, 22 and 24 (STR1, STR13, STR22 and STR24, respectively) in FVIII.

Our analysis revealed 7 different alleles for STR1, 10 for STR13, 7 for STR22 and 9 for STR24. The heterozygosity rate (HR) for STR1, 13, 22 and 24 was 34.6%, 49.6%, 43.6% and 38.2%, respectively. The HR was 75.0% (165/220) when these four markers were combined. Prenatal diagnosis was made for five male foetuses. Four foetuses were identified as affected ones of HA. The STR results were consistent with the data we obtained by PCR of St14 VNTR (DXS52) and DNA sequencing, which showed that one foetus harbours a mutation in exon12 (1804C > T) in FVIII.

This study demonstrates that multiplex fluorescent analysis of four STRs is a rapid and simple method to perform genetic diagnosis of HA in families with a history of this disorder.