Background: The solute carrier family 45-member 2 (SLC45A2) gene, located on chromosome 5p13.2, is involved in melanin biosynthesis. Single-nucleotide variants (SNVs) in this gene are associated with skin, eye, and hair color variations in the population. SNVs p.L374F (C/T) and p.E272K (C/G) are additionally associated with protection against melanoma. Objectives: This study aimed to evaluate the association of SNVs p.L374F and p.E272K with the development of melanoma in a sample of individuals from Bogotá, Colombia. Methods: In this case-control study, DNA samples were obtained from individuals after signing an informed consent form. Genotyping was performed by real-time polymerase chain reaction high-resolution melting (PCR-HRM). Results: Phototype II was found in 19% of the subjects, phototype III in 70%, and phototype IV in 11%. Eighty percent of the subjects had brown eyes and dark brown hair color. Both SNVs were in Hardy-Weinberg equilibrium. The p.Glu272Lys variant was found to be a protective factor for melanoma, while the p.Phe374Leu variant was found to be a risk factor. The study also found that a CG haplotype was a risk factor for melanoma [odds ratio (OR), 2.75; 95% CI, 1.22 - 6.22; P = 0.021]. The study also found a strong correlation between variants and phototypes, as well as the sex of the patients. The study also analyzed the impact of these variants on the protein structure and found that the p.Phe374Leu variant has a probable pathogenic effect on the function of the protein. Conclusions: The frequencies found for the SLC45A2 gene variants are consistent with other studies conducted in the Latin American population, where the predominant phototypes are II and III. The CG haplotype is associated with a higher risk of melanoma.

Background Leprosy is a chronic infectious disease caused by Mycobacterium leprae. The development of leprosy involves several factors, including the causative agent, the individual host’s immune response, environmental factors, and the genetic background of the host. Specifically, the host’s innate immune response, encoded by genes, determines their susceptibility to developing leprosy post-infection. Polymorphic variants in the nucleotide-binding oligomerization domain 2 (NOD2) gene are associated with leprosy among populations in a variety of endemic areas around the world. Colombia, a country located in the tropical zone, has several leprosy-endemic regions, including Norte de Santander. The aim of this study was to analyze the rs7194886, rs2111234, rs3135499, and rs8057341 single nucleotide polymorphisms (SNPs) in the NOD2 gene using a case-control study to determine whether they confer greater or lesser susceptibility to the development of leprosy. Methodology The TaqMan qPCR amplification system was used for SNPs detection. Findings An association between the A-rs8057341 SNP (p = 0,006286) and resistance to leprosy was found. However, the rs3135499 (p = 0,9063) and rs2111234 (p = 0.1492) were not found to be associated with leprosy susceptibility. In addition, the rs7194886 SNP was not found to be in Hardy-Weinberg equilibrium (HWE) in the study population. The GAG haplotype, consisting of SNPs rs2111234-G, rs3135499-A, and rs8057341G, acts as a susceptibility factor for the development of leprosy in women. SNPs rs3135499 and rs8057341 are functionally related to decreased NOD2 expression according to an in-silico analysis. Conclusions The SNPs rs8057341-A was related with resistance to leprosy and the haplotype rs2111234-G, rs3135499-A and rs8057341-G SNPs was related with susceptibility in the Norte de Santander Colombia, studied population.