title: A common F13A1 intron 1 variant IVS1+12(A) is associated with mild FXIII deficiency in Caucasian population.
abstract: Mild factor XIII deficiency is an underdiagnosed coagulation disorder. Considering the large number of coding and non-coding polymorphisms identified in the F13A1 gene, there is a possibility that some of these might result in alterations of plasma FXIII levels and cause mild FXIII deficiency. Recently, a homozygous F13A1 gene intron 1 variant (IVS1+12C>A) was found in a patient with FXIII deficiency. In vitro expression studies for this variant demonstrated its lowering effect on FXIII levels. In order to determine the impact of this variant on a population level, we analysed the prevalence of this variant in three clinically and genetically defined population cohorts: an apparently healthy control cohort C1 (n = 102), a mild FXIII deficiency cohort C2 with no detectable F13A1 or F13B gene mutations (n = 183) and a mild FXIII-A deficiency cohort C3 exhibiting heterozygous F13A1 mutations (n = 37). FXIII activity was determined using photometric assay on plasma samples. The F13A1 gene intron 1 variant was analysed by direct sequencing. The C1 cohort showed a normal distribution of FXIII activity (mean 114.1 ± 20.86%). Mean FXIII activity levels for the C2 and C3 cohorts were 54.45 ± 11.12% and 44.21 ± 10.16%, respectively. The frequencies of minor allele (A) were 0.07 in C1 cohort, 0.19 in C2 cohort and 0.11 in C3 cohort. The difference in minor allele frequencies for the C1 and C2 cohorts were highly significant (p < 0.001). The greater frequency of the IVS1+12(A) variant among C2 cohort patients suggests that this polymorphism is associated with mild FXIII deficiency.
authors.affiliation: Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany. vytautas.ivaskevicius@ukb.uni-bonn.de
authors.forename: Vytautas
authors.initials: V
authors.lastname: Ivaskevicius
authors.forename: Arijit
authors.initials: A
authors.lastname: Biswas
authors.forename: Anne
authors.initials: A
authors.lastname: Thomas
authors.forename: Sophie
authors.initials: S
authors.lastname: Lyonga
authors.forename: Hannelore
authors.initials: H
authors.lastname: Rott
authors.forename: Susan
authors.initials: S
authors.lastname: Halimeh
authors.forename: Guenther
authors.initials: G
authors.lastname: Kappert
authors.forename: Robert
authors.initials: R
authors.lastname: Klammroth
authors.forename: Ute
authors.initials: U
authors.lastname: Scholz
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Eberl
authors.forename: Ursula
authors.initials: U
authors.lastname: Harbrecht
authors.forename: Christine
authors.initials: C
authors.lastname: Gnida
authors.forename: Hans-Joerg
authors.initials: HJ
authors.lastname: Hertfelder
authors.forename: Natascha
authors.initials: N
authors.lastname: Marquardt
authors.forename: Johannes
authors.initials: J
authors.lastname: Oldenburg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D002648:Child; D002675:Child, Preschool; D005176:Factor XIII / Q000235:genetics*; D005177:Factor XIII Deficiency / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007223:Infant; D007438:Introns / Q000235:genetics; D008297:Male; D008875:Middle Aged; D017422:Sequence Analysis, DNA; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: C064015:factor XIII subunit A; D005176:Factor XIII