Association between polymorphism at codon 469 of the ICAM-1 gene and Henoch-Schönlein purpura in an Iranian cohort.

Henoch-Schönlein purpura (HSP) is a common form of IgA1-mediated blood vessel inflammation affecting mainly children. Intercellular adhesion molecule-1 (ICAM-1) gene polymorphisms have been shown to be associated with HSP in different populations; in this study, we investigated its potential association and influence on the development of severe complications in Iranian HSP patients. Twenty-three patients diagnosed with IgAV/HSP according to the criteria of the American College of Rheumatology (ACR) with 53 age- and sex-matched control subjects were referred to us. Cases and controls were genotyped using Sanger sequencing. Based on our research data, we found an association between codon 469 K/E of the ICAM1 gene and risk of HSP. Our results revealed that KK genotype and allele K are more common in control than in the HSP group, therefore the subjects with KK genotype are protected against HSP. Our data also suggested that the genotype EE is associated with higher risk of HSP progression compared to KK genotype.

DNA repair-related heritable photosensitivity syndromes: Mutation landscape in a multiethnic cohort of 17 multigenerational families with high degree of consanguinity.

Inherited photosensitivity syndromes are a heterogeneous group of genetic skin disorders with tremendous phenotypic variability, characterized by photosensitivity and defective DNA repair, especially nucleotide excision repair. A cohort of 17 Iranian families with heritable photosensitivity syndromes was evaluated to identify their genetic defect. The patients' DNA was analyzed with either whole-exome sequencing or RNA sequencing (RNA-Seq). The interpretations of the genomic results were guided by genome-wide homozygosity mapping. Haplotype analysis was performed for cases with recurrent mutations. RNA-Seq, in addition to mutation detection, was also utilized to confirm the pathogenicity. Thirteen sequence variants, including six previously unreported pathogenic variants, were disclosed in 17 Iranian families, with XPC as the most common mutated gene in 10 families (59%). In one patient, RNA-Seq, as a first-tier diagnostic approach, revealed a non-canonical homozygous germline variant: XPC:c.413-9 T > A. The Sashimi plot showed skipping of exon 4 with dramatic XPC down-expression. Haplotype analysis of XPC:c.2251-1 G>C and XPC:1243 C>T in four families showed common haplotypes of 1.7 Mb and 2.6 Mb, respectively, denoting a founder effect. Lastly, two extremely rare cases were presented in this report: a homozygous UVSSA:c .1990 C>T was disclosed, and ERCC2-related cerebro-oculo-facio-skeletal (COFS) syndrome with an early childhood death. A direct comparison of our data with the results of previously reported cohorts demonstrates the international mutation landscape of DNA repair-related photosensitivity disorders, although population-specific differences were observed.