Admixture of beneficial and unfavourable variants of GLCCI1 and FCER2 in Roma samples can implicate different clinical response to corticosteroids

Abstract

Variants of glucocorticoid induced transcript 1 (GLCCI1) result decreased response to inhaled corticosteroids, while intronic variant of low-affinity IgE receptor (FCER2) is associated with exacerbation rates in children with asthma. We examined the ethnic differences, allele and genotype frequencies of two linked single nucleotide polymorphisms (rs37972, rs37973) of GLCCI1 and rs28364072 intronic variant of FCER2 gene in average Roma and Hungarian population. A study population of 474 healthy Roma and 397 Hungarian subjects were characterized for GLCCI1 and FCER2 polymorphisms using real time polymerase chain reaction (PCR) assay and PCR-restriction fragment length polymorphism method. The rs37972 and rs37973 polymorphisms in GLCCI1 were found in 100% linkage disequilibrium both in Romas and in Hungarians. We found significant differences between the two groups regarding both minor allele frequencies (54.5 vs. 43.8%, p ≤ 0.01) and homozygous genotype (31.6 vs. 21.3%, p ≤ 0.01) of GLCCI1. For FCER2 rs28364072 the homozygous variant genotype was present in 2.8% in Romas, while in Hungarians it was 5.8% (p = 0.032). The opposite changes of these two polymorphisms strongly suggest that contrary current belief analyses of GLCCI1 variants are insufficient for personalised glucocorticoid therapies in different populations.