A common origin of the 4143insA ADAMTS13 mutation

Area of Science:

• Genetics
• Hematology
• Molecular Biology

Background:

• Severely deficient activity of ADAMTS13 (von Willebrand Factor cleaving metalloprotease) causes thrombotic thrombocytopenic purpura (TTP).
• The spectrum of ADAMTS13 mutations associated with congenital TTP is heterogeneous, with numerous mutations reported across the gene.
• The 4143insA mutation is notable for its specific geographic concentration.

Purpose of the Study:

• To investigate the geographic distribution and genetic background of the 4143insA mutation in ADAMTS13.
• To identify additional mutations associated with hereditary ADAMTS13 deficiency.

Main Methods:

• Identified the 4143insA mutation in eleven additional patients from Norway, Sweden, Poland, Germany, the Czech Republic, and Australia.
• Established ADAMTS13 haplotypes using 17 polymorphic intragenic markers.
• Analyzed mutation spectrum and identified novel mutations (C347S, P671L, R1060W) and a known mutation (R507Q).

Main Results:

• The 4143insA mutation was found in patients of Northern and Central European ancestry, suggesting a common genetic origin.
• Haplotype analysis revealed identical haplotypes linked to the 4143insA mutation in all informative families.
• Three novel candidate mutations and one known mutation were identified during the study.

Conclusions:

• The 4143insA mutation has a common genetic background.
• This mutation is frequent among patients with hereditary ADAMTS13 deficiency in Northern and Central European countries.