Prenatal diagnosis of factor X deficiency using a combination of direct mutation detection and linkage analysis with an intragenic single nucleotide polymorphism.

Objective: To present a family in which it was possible to perform prenatal diagnosis for recessively inherited factor X deficiency using both direct mutation detection as well as linkage analysis.

Methods: In a family where both parents were known to be carriers of factor X deficiency, fetal DNA was obtained from an ongoing pregnancy by CVS in the first trimester. Direct DNA sequencing was used to detect a previously identified factor X mutation, and linkage analysis using a single nucleotide polymorphism (SNP) was used to follow the segregation of the other parent's factor X alleles.