title: Serum amyloid A1 -13 T/C alleles in Turkish familial Mediterranean fever patients with and without amyloidosis.
abstract: Previously reported studies concerning the effect of homozygosity of the 1.1 allele of the SAA gene found a correlation between this haplotype and susceptibility to amyloidosis in FMF patients. Another report revealed a strong association between SAA1 -13T/C and secondary amyloidosis in the rheumatoid arthritis patient group. In this study, we aimed to determine the effect of SAA1 -13T/C in FMF patients with and without amyloidosis. The study cohort, consisting of 166 patients with FMF was divided into two groups, according to the presence (n=66) or absence (n=100) of renal amyloidosis at study entry. MEFV gene mutation analysis and allelic variant of SAA1 gene -13 T/C was analyzed according to the previously described techniques. SAA1 -13 T allele frequencies were 0.5816, 0.23 and 0.4242 in controls, FMF patients and FMF-amyloidosis patients respectively. The difference between controls vs. FMF patients and FMF-amyloidosis patients were 0.0002 and 0.1673 respectively. It was 0.0071 for FMF-patients vs. FMF-amyloidosis. When 694 M/V homozygous nonamyloid-FMF group was compared with 694 M/V carriers of the FMF-amyloidosis group, the difference was 0.049. When carrying TT allele was considered, the difference between controls vs. FMF patients and FMF-amyloidosis patients were 0.0001 and 0.58. It was 0.0003 for FMF patients vs. FMF-amyloidosis. When 694 M/V homozygous nonamyloid-FMF group was compared with 694 M/V carriers of the FMF-amyloidosis group, the difference was 0.03. Carrying SAA -13T in homozygote state revealed a 7.9 (95% CI 3.6 -17.5) fold risk for the occurrence of amyloidosis when compared with FMF patients without amyloidosis. This was 8.75 (95% CI 3.0 - 25.1) when 694 M/V homozygotes were taken into consideration. Our data revealed that the genotype SAA1 -13T has at least an effect on the development of amyloidosis. As more data on this polymorphism accumulate, we will understand its effect on the pathogenesis of amyloidosis in FMF.
authors.affiliation: Pediatric Molecular Genetics Department, Ankara University, School of Medicine, Ankara, Turkey. akar@medicine.ankara.tr
authors.forename: Nejat
authors.initials: N
authors.lastname: Akar
authors.forename: Metis
authors.initials: M
authors.lastname: Hasipek
authors.forename: Ayşenur
authors.initials: A
authors.lastname: Oztürk
authors.forename: Ece
authors.initials: E
authors.lastname: Akar
authors.forename: Mustafa
authors.initials: M
authors.lastname: Tekin
mesh_terms: D000686:Amyloidosis / Q000150:complications / Q000235:genetics*; D016022:Case-Control Studies; D015331:Cohort Studies; D003598:Cytoskeletal Proteins / Q000235:genetics; D010505:Familial Mediterranean Fever / Q000150:complications* / Q000235:genetics*; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000150:complications / Q000235:genetics*; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D000071198:Pyrin; D000685:Serum Amyloid A Protein / Q000235:genetics*; D014421:Turkey
chemical_list: D003598:Cytoskeletal Proteins; C000604192:MEFV protein, human; D000071198:Pyrin; D000685:Serum Amyloid A Protein