High frequency of (TG)mTn variant tracts in the cystic fibrosis transmembrane conductance regulator gene in men with high semen viscosity.
OBJECTIVE
To evaluate a possible correlation between abnormal semen consistency and cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations and variant tracts.


METHODS
Study of CFTR mutations and variant tracts in men with high semen viscosity as compared with normospermic men.


METHODS
University-based centers for andrology, clinical biochemistry, and cystic fibrosis.


METHODS
Forty-six male partners from infertile couples with sine causa high semen viscosity compared with 72 normospermic men.


METHODS
Semen sample collection.


METHODS
We obtained the (TG)mTn polymorphic tracts and a panel of 31 mutations of CFTR, semen viscosity, and semen variables.


RESULTS
The frequencies of the (TG)12 and T5 variant alleles were statistically significantly higher in men with high semen viscosity (17.4% and 7.6%, respectively) than in the normospermic control group (6.9% and 1.4%, respectively). The frequency of the genotypes carrying (TG)12 or T5 was statistically significantly higher in men with high semen viscosity (39.1%) than in the normospermic control group (16.7%). Four men with high semen viscosity showed the variant (TG)12T5 haplotype; one of these men presented variant tracts on both alleles. None of the normospermic controls showed a (TG)12T5 haplotype.


CONCLUSIONS
Semen hyperviscosity could be considered a "minimal clinical expression" of cystic fibrosis; CFTR gene sequence variations may constitute the genetic basis for this disease.
Rossi
Tiziana
T
Department of Medical Physiopathology, University of Rome La Sapienza, Rome, Italy.
Grandoni
Francesco
F
Mazzilli
Fernando
F
Quattrucci
Serena
S
Antonelli
Mariano
M
Strom
Roberto
R
Lucarelli
Marco
M
D000483:Alleles; D016022:Case-Control Studies; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D005787:Gene Frequency; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D009154:Mutation; D011110:Polymorphism, Genetic; D012661:Semen / Q000737:chemistry*; D014783:Viscosity
C505032:CFTR protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator