Italian familial defective apolipoprotein B patients share a unique haplotype with other Caucasian patients

Area of Science:

• Genetics
• Biochemistry
• Cardiovascular Medicine

Background:

• Familial hypercholesterolemia is a common genetic disorder characterized by high cholesterol levels.
• Familial defective apolipoprotein B-100 (apo B-100) is a significant genetic cause of hypercholesterolemia.
• Specific mutations in the apo B gene, particularly around codon 3500, lead to defective apo B-100.

Purpose of the Study:

• To investigate the prevalence of familial defective apo B-100, specifically the Arg3500Gln mutation, in Italian populations.
• To identify and characterize new cases of familial defective apo B-100 in Italy.
• To analyze the apo B gene haplotype co-segregating with the Arg3500Gln mutation in Italian families.

Main Methods:

• Screening of probands diagnosed with Familial Hypercholesterolemia from mainland Italy and Sicily.
• Genetic analysis to identify specific mutations (Arg3500Gln, Arg3531Cys) in the apo B gene.
• Haplotype analysis of the apo B gene in affected families.

Main Results:

• Three new Italian families with the Apo B Arg3500Gln mutation were identified (one from Liguria, two from Sicily).
• The prevalence of the Apo B Arg3500Gln mutation was found to be low (0.28% in mainland Italy, 0.65% in Sicily).
• The Apo B Arg3531Cys mutation was not detected in any of the screened individuals.
• The Arg3500Gln mutation consistently co-segregated with a specific apo B haplotype in Italian families, consistent with previous findings in Caucasian populations.

Conclusions:

• Familial defective apo B-100 due to the Arg3500Gln mutation is present but rare in the studied Italian populations.
• The identified apo B haplotype provides a genetic marker for this mutation in Italy.
• Further research may be warranted to understand the geographical distribution and clinical impact of this mutation in diverse populations.