Аннотация:Sex hormone-binding globulin (SHBG) is the specific plasma transport protein for sex steroid hormones in humans. Considerable variation in SHBG plasma concentration exists between individuals, irrespective of gender, body weight, or thyroid status. In the present work, the influence of carbohydrate chains on the half-life of human SHBG (hSHBG) was investigated using a rabbit model. A variant hSHBG, with a point mutation in exon 8 (GAC → AAC) encoding an amino acid substitution (Asp327Asn), which introduces an additional consensus site for N-glycosylation, has recently been identified. This mutation suppresses a recognition site for the restriction enzyme Bbs-I, allowing the development of a simple restriction-fragments length polymorphism (RFLP) screening procedure. In a population of patients (272 female and 49 male) consulting in our Endocrinology Clinic, 48 patients (41 female and 7 male) were heterozygous for the variant hSHBG allele and 3 (2 female and 1 male) were homozygous. In this population, the total variant allele frequency was 0.083. The hSHBG genotype, as determined by RFLP, corresponded in all cases to the phenotype as determined by the migration profile of hSHBG by Western blot analysis.
