The prevalence of FDBArg3500Gln mutation in hypercholesterolaemic Polish subjects (3.7%) seems to be similar to the frequency reported in other Caucasian hypercholesterolaemic populations.
Eight (5.1%) unrelated individuals were found to be heterozygous for the FDBR3500Q mutation, including two (3.7%) of those 54 classified clinically as having FH.
By screening two groups of probands, clinically diagnosed as having Familial Hypercholesterolemia (700 from mainland Italy and 305 from Sicily), the prevalence of familial defective apolipoprotein B-100 due to Arg3500Gln was found to be very low (0.28% and 0.65%, respectively).
The Arg3500Gln mutation in the apolipoprotein B gene, which is responsible for familial defective apolipoprotein B-100 and is present in approximately 1 in 1000 persons in Denmark, causes severe hypercholesterolemia and increases the risk of ischemic heart disease.
Familial defective apolipoprotein B-100 (FDB) is a dominantly inherited disorder caused by the substitution of glutamine for arginine at position 3500 in apo B-100.
Familial defective apolipoprotein B-100 (FDB) is a genetic disorder caused by a substitution of glutamine for arginine at residue 3500 of the apolipoprotein B-100 molecule.
In our FH probands, four cases of FDB (R3500Q mutation) were diagnosed with allele-specific PCR, and the mutation was also detectable in five cases out of seven living family members.
Population studies suggest that approximately 0.1% of Northern Europeans and US Caucasians carries the R3500Q variant in APOB most commonly associated with FDB; in addition, the APOB R3500 W variant is known to make a significant contribution to familial hypercholesterolemia (FH) among East Asians.
Additional genotyping revealed the presence of R3500Q, the mutation responsible for familial defective apolipoprotein B-100, which was also strongly associated with LDL-C in the replication sample (P < 10(-36)).