RESUMO
Flax, Linum usitatissimum L., is a valuable multi-purpose plant, and currently, its genome is being extensively investigated. Nevertheless, mapping of genes in flax genome is still remaining a challenging task. The cellulose synthase (CesA) multigene family involving in the process of cellulose synthesis is especially important for metabolism of this fiber crop. For the first time, fluorescent in situ hybridization (FISH)-based chromosomal localization of the CesA conserved fragment (KF011584.1), 5S, and 26S rRNA genes was performed in landrace, oilseed, and fiber varieties of L. usitatissimum. Intraspecific polymorphism in chromosomal distribution of KF011584.1 and 5S DNA loci was revealed, and the generalized chromosome ideogram was constructed. Using BLAST analysis, available data on physical/genetic mapping and also whole-genome sequencing of flax, localization of KF011584.1, 45S, and 5S rRNA sequences on genomic scaffolds, and their anchoring to the genetic map were conducted. The alignment of the results of FISH and BLAST analyses indicated that KF011584.1 fragment revealed on chromosome 3 could be anchored to linkage group (LG) 11. The common LG for 45S and 5S rDNA was not found probably due to the polymorphic localization of 5S rDNA on chromosome 1. Our findings indicate the complexity of integration of physical, genetic, and cytogenetic mapping data for multicopy gene families in plants. Nevertheless, the obtained results can be useful for future progress in constructing of integrated physical/genetic/cytological maps in L. usitatissimum which are essential for flax breeding.
RESUMO
The aim of the study was to evaluate the clinical and genetic predictors of AA amyloidosis in patients with familial Mediterranean fever (FMF). We retrospectively studied 170 Armenian patients who were admitted to the two tertiary centers in 2003-2014. The diagnosis of amyloidosis that was suspected clinically (new proteinuria or nephrotic syndrome) was confirmed histologically. Screening for MEFV gene mutations was performed in 70 patients. The most common genotype was M694V/M694V (in 36 % of patients). Biopsy-proven AA amyloidosis was found in 102 (60 %) of 170 patients. AA amyloidosis was diagnosed in 17 (68 %) of 25 patients with homozygous M694V mutation, 17 (53 %) of 32 patients with heterozygous M694V allele and 4 (31 %) of 13 patients with other MEFV gene mutations. The M694V homozygosity and heterozygosity were associated with increased risk of AA amyloidosis, but this association did not reach statistical significance (odds ratio 2.43; 95 % CI 0.87-6.76, and 3.33; 0.91-12.1, respectively). Male gender, early onset of disease, severity of FMF, frequent attacks, peritonitis, pleuritis and erysipelas-like erythema also did not predict AA amyloidosis development. Recurrent arthritis was the only clinical finding that was significantly associated with AA amyloidosis (odds ratio 2.28; 95 % CI 1.17-4.42). Involvement of the joint synovial membrane, that is capable of active serum amyloid A production, is the main predictor of renal amyloidosis in FMF.
