hRDH-E2 gene polymorphisms, variable transcriptional start sites, and psoriasis

Area of Science:

• Biochemistry
• Genetics
• Dermatology

Background:

• The short-chain alcohol dehydrogenase/reductase (SDR) family enzyme, hRDH-E2, is vital for converting retinol to retinaldehyde, a key step in retinoic acid synthesis essential for skin health.
• Elevated hRDH-E2 mRNA levels were previously observed in psoriatic skin compared to healthy skin, suggesting a potential role in the disorder.
• The hRDH-E2 gene's location on Chromosome 8 positions it as a functional and positional candidate gene for psoriasis.

Purpose of the Study:

• To investigate the genetic variations within the hRDH-E2 gene and their association with psoriasis.
• To identify and characterize polymorphisms in the hRDH-E2 gene, including coding and non-coding regions.

Main Methods:

• Direct sequencing of polymerase chain reaction (PCR)-amplified DNA from psoriatic patients and healthy controls to identify polymorphisms.
• Identification of one microsatellite marker and six single nucleotide polymorphisms (SNPs), including a nonsynonymous SNP in the second exon.
• Genotyping of identified polymorphisms in a larger cohort of 100 Japanese psoriatic patients and 120 controls.

Main Results:

• Several polymorphisms were identified in the hRDH-E2 gene, including single nucleotide polymorphisms (SNPs) and a microsatellite marker.
• One identified SNP resulted in an amino acid change from Arginine to Tryptophan in the hRDH-E2 protein.
• No statistically significant differences in genotype or allele frequencies of the detected hRDH-E2 polymorphisms were found between psoriatic patients and controls.

Conclusions:

• The identified polymorphisms in the hRDH-E2 gene do not appear to contribute to the etiology of psoriasis.
• These hRDH-E2 gene polymorphisms may have relevance in the pathogenesis of diseases affecting other tissues.