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.


RESULTS
Our studies predicted the fetus in question to be a heterozygote carrier of factor X deficiency, and this was demonstrated to be correct at birth.


CONCLUSIONS
This is the first reported case of prenatal diagnosis of factor X deficiency. In addition, this case demonstrates the remarkable utility of SNPs in linkage analysis of rare genetic disorders.
Camire
Rodney
R
Department of Pediatrics, The University of Pennsylvania, School of Medicine and The Children's Hospital of Philadelphia, Philadelphia, USA.
Ann Denchy
Ruth
R
Day
George A
GA
Lanzano
Patricia
P
Sheth
Sujit
S
Brown
Stephen
S
D000328:Adult; D015193:Chorionic Villi Sampling; D004247:DNA / Q000097:blood; D004252:DNA Mutational Analysis / Q000379:methods*; D005171:Factor X Deficiency / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D005312:Fetal Blood; D008040:Genetic Linkage; D006579:Heterozygote; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011247:Pregnancy; D011261:Pregnancy Trimester, First
D004247:DNA