Background:
Investigation of rare bleeding disorders in Latin-America.
Objective:
The report of a new case of FX deficiency due to a compound heterozygosis.
Methods:
Accepted clotting procedures were used. Sequencing of DNA was carried out by means
of Applied Biosystems Instruments.
Results:
A compound heterozygote due to the association of a new mutation (Gla72Asp) with an
already known mutation (Gly154Arg) of the FX gene is reported. The proposita is a 38 year old female
who had a moderate bleeding tendency (menorrhagia, epistaxis, easy bruising). The proposita has
never received substitution therapy but in the occasion of a uterine biopsy. The mother was
asymptomatic but was a heterozygote for the new mutation. The father was asymptomatic but had
deserted the family and could not be investigated. After this abandonment the mother of the proposita
re-married with an asymptomatic man and she gave birth to a son who was asymptomatic but was also
heterozygous for the new mutation (Gla72Asp). As a consequence it has to be assumed that the first
husband of the mother of the proposita was heterozygous for the known mutation (Gly154Arg).
Conclusion:
This is the third case of a new mutation in the FX gene reported, during the past few
years, in Argentina.
A New Mutation in the Promoter Region of the PAX8 Gene Causes True Congenital Hypothyroidism with Thyroid Hypoplasia in a Girl with Down's Syndrome