Sorted By Test Name - Mayo Medical Laboratories

FIXKM
84320
Interpretation: An interpretive report will be provided that includes specimen information, pedigree
information (when appropriate), assay information, whether test results are consistent with a diagnosis or
positive carrier status, and an estimate of residual carrier risk, when appropriate.
Reference Values:
An interpretive report will be provided which will include a risk analysis (probability of being a carrier).
Clinical References: 1. Castaldo G, D'Argenio V, Nardiello P, et al: Haemophilia A: molecular
insights. Clin Chem Lab Med 2007;45(4):450-461 2. Lakich D, Kazazian Jr HH, et al: Inversions
disrupting the factor VIII gene are a common cause of severe hemophilia A. Nature Genetics
1993;5(3):236-241 3. Antonarakis SE, Rossiter JP, Young M, et al: Factor VIII gene inversions in severe
hemophilia A: results of an international consortium study. Blood 1995;86(6):2206-2212
Hemophilia B, Factor IX Gene Known Mutation Screening
Clinical Information: Hemophilia B, factor IX deficiency, is an X-linked recessive bleeding disorder
with an incidence of about 1 per 30,000 live male births. This occurs as a result of mutation(s) in factor IX
(fIX) gene. As many as 1/3 of hemophiliacs have no affected family members, reflecting a high mutation
rate (de novo mutations). Hemophilia B affects males, however, all male offspring will be normal and
although all female offspring will be obligatory carriers, they rarely have symptomatic bleeding. In
contrast, female offspring of carriers of hemophilia B have a 50% chance of being carriers themselves,
and each male offspring has a 50% chance of being affected. Based on factor IX activity, hemophilia B is
classified into severe (factor IX activity