Determination of haemophilia A carrier status from hair samples using polymerase chain reaction technique.

The usefulness of intragenic restriction fragment length polymorphisms (RFLPs) for BclI, HindIII and XbaI, adapted for polymerase chain reaction (PCR), was tested for the detection of haemophilia A carrier status in the consultant of a family in which only haematological information was available on the inheritance of the trait. Hair follicles were used as the non-invasive source of DNA. The mother was found to be homozygous for BclI and heterozygous for HindIII sites, whereas her status as regards informativeness could not be established for XbaI. On the basis of HindIII RFLP, the daughter was found to be a carrier of the haemophilia trait. This was confirmed by sequencing the amplified intron 19 of the mother and the daughter. The RFLP for XbaI did not appear to be suitable for carrier detection using PCR due to the difficulty of establishing homozygosity or heterozygosity from the results of digestion of the amplified product.