[NOD2 novel mutations in Iranian Crohn's patients]

ABSTRACT

Despite the reported role of three common mutations of the CARD15/NOD2 gene including R702W, G908R and 1007fs in Crohn's disease [CD], only about 30% of Iranian CD patients carry one of these three variants [R702W]. The aim of this study was to screen the hot points of NOD2 gene to find any novel sequence variations in Iranian patients with CD. Eighty non-related Crohn's patients from Iranian origin, referred to a tertiary center in a three-year period [2006-2009], were enrolled in this study. The hot points of NOD2 gene [including exons 4 and 8] were evaluated by direct sequencing after amplification of related sequences with polymerase chain reaction [PCR]. A total of 17 sequence variations were identified among these exons of NOD2 gene including 7 novel ones. Three of these new mutations had an allele frequency more than 5%. All new mutations were a consequence of a single nucleotide change, 4 resulted in an aminoacid change while one formed a stop coden. No deletion or insertion mutation was observed in this part of the gene. This study demonstrated the existence of uncommon NOD2 variants in Iranian patients with CD. It is possible that these mutations play a role in susceptibility to CD in Iranian population