Molecular genetic studies in monogenic and polygenic human diseases

The main goal of this study was to determine and characterise the types of mutations in two monogenic human disorders: cystic fibrosis (CF) and Duchenne/Becker muscular dystrophy (DMD, BMD) and the susceptibility allele frequency in a polygenic disease: type I insulin-dependent diabetes mellitus (IDDM). After analysing 220 chromosomes for mutations in the CF (Cystic Fibrosis Transmembrane Conductance Regulator = = CFTR) gene, ΔF508 mutation was most abundant (41%) and out of the non-ΔF508 CF mutations 5% was identified as G542X, G551D, R553X, N1303K and W1282X The CF haplotype analysis by using linked markers to the CFTR gene revealed that the CF “B” haplotype occurred in 66.7% of patients, and this haplotype was 57.2% in patients carrying the ΔF508 mutation. Prenatal genetic diagnosis for CF was performed in 10 fetuses: 3 were affected, 6 were carriers, and 1 without any CF mutation.