An association of this polymorphism with habitual miscarriage was revealed; the 4a allele frequency is significantly higher in the case of habitual miscarriage than in the control. Genotypes 4b/4a are considered as undesirable variants.
It encodes an enzyme that determines the nitric oxide level in the wall of blood vessels. The allele 4a is associated with arterial hypertension, the decreased elasticity of the vascular wall and myocardial hypertrophy.
It encodes an enzyme that determines the nitric oxide level in the wall of blood vessels. The allele 4b is associated with endurance; the allele 4a is associated with arterial hypertension, the decreased elasticity of the vascular wall and myocardial hypertrophy.