SUMO1 as a candidate gene for non-syndromic cleft lip with or without cleft palate: no evidence for the involvement of common or rare variants in Central European patients

Abstract Objective Studies in mice and humans have suggested that SUMO1 , which codes for the small ubiquitin-related modifier 1 (SUMO1), is a promising candidate gene for non-syndromic cleft lip with or without cleft palate (NSCL/P). To investigate the possible involvement of this gene in NSCL/P patients from Central Europe, we performed: (i) a case control association study, and (ii) a resequencing study. Methods Genotyping and the subsequent single marker and haplotype association analyses were performed for 413 NSCL/P patients and 412 controls. A total of 17 tagging single-nucleotide polymorphisms (SNPs) were used. In the resequencing study, the complete coding region and splice sites were sequenced in 65 index patients from multiply affected families. Results One of the 17 tested SNPs (rs16838917) had a borderline significant P -value of 0.0416 in the single-marker association analysis. However, this result did not withstand correction for multiple testing ( P corr  = 0.707). No association was observed for any haplotypic marker combination. Sequencing failed to identify any novel rare sequence variants. Conclusions The results of the present study do not support the hypothesis that common or rare variants in SUMO1 play a significant role in the development of NSCL/P in Central-European patients. However, smaller effects of common variants or the presence of rare high penetrance mutations in other non-investigated familial cases cannot be excluded. Further analysis of SUMO1 in independent samples from Central European and other populations is therefore warranted.