rs1426654

This study identified rs41305272, a predicted miR-330-3p target site SNP in MAP2K5, as associated with anxiety and depressive disorders in 6,725 European-American and African-American subjects. The T-allele was significantly associated with agoraphobia (OR=2.22, p=0.0004 combined sample), panic disorder (OR=1.95, p=0.002), and major depressive disorder (OR=1.48, p=0.01). The rs41305272 SNP is in linkage disequilibrium with a restless legs syndrome GWAS variant and showed pathway enrichment for nervous system development genes.

This functional study examines SLC24A5 (NCKX5), a gene associated with skin pigmentation variation via the rs1426654 A111T variant (A111T substitution). Using siRNA knockdown in normal human melanocytes, the authors demonstrate that SLC24A5 regulates MC1R expression and surprisingly affects cholesterol metabolism genes, with knockdown increasing cellular cholesterol content, suggesting NCKX5 influences skin pigmentation through a novel mechanism involving sterol homeostasis rather than direct melanogenesis regulation.

This case-control study of 722 lung cancer cases and 929 controls examined 240 SNPs in DNA repair and cell cycle control pathway genes among smokers. Thirty-eight SNPs were associated with lung cancer risk at P<0.05, with strongest associations in GTF2H4 (rs2074508), LIG1 (rs10500298), PARP1 (rs747658, rs3219073), and XRCC1 (rs1799782, rs3213255). A genetic risk score combining 31 SNPs showed 3.44-fold increased risk in the highest versus lowest quartile.

This genome-wide association study of skin color in 285 Puerto Rican Hispanics/Latinos identified 82 suggestive variants, of which 14 replicated in 373 African Americans. Meta-analysis confirmed associations at SLC24A5 (rs1426654, p=2.62×10⁻¹⁴), SLC45A2 (rs16891982, p=9.71×10⁻¹⁰), and revealed a novel locus in the BEND7/PRPF18 intergenic region (rs6602666, p=4.58×10⁻⁹) that is prevalent in African-descent populations but absent in Europeans and Native Americans.

This genome-wide association study (GWAS) of pigmentary traits in East Asian populations (N=305 skin, N=342 iris) identifies a genome-wide significant signal for iris color in the OCA2 region, with rs1800414 (His615Arg) explaining 11.9%, 10.4%, and 6% of variation in b*, a*, and L* coordinates respectively. While no genome-wide significant signals were detected for skin pigmentation, rs2373391 in ZNF804B was replicated in independent Chinese samples (p=0.003).

This study demonstrates that human hair color can be predicted from DNA variants with high accuracy using a multinomial logistic regression model. A subset of 13 genetic markers from 11 genes (MC1R, HERC2, IRF4, TYR, EXOC2, SLC45A2, TYRP1, OCA2, SLC24A4, KITLG, ASIP) predicted hair color categories in Polish Europeans with AUC values of 0.93 for red hair, 0.87 for black hair, 0.82 for brown hair, and 0.81 for blond hair. MC1R variants showed the strongest association with red hair (OR=12.64 for R variants, P=2.5×10⁻¹⁷), while rs12913832 in HERC2 was significantly associated with darker hair colors (OR=3.33 for black, P=4.3×10⁻⁶).

This candidate gene association study examined five CHRNA4 SNPs in 1,249 European-Americans and 1,790 African-Americans to evaluate associations with smoking behavior. The synonymous SNP rs1044394 was significantly associated with nicotine dependence (DSM-IV ND: P=0.001; FTND: P=0.01) and remained significant after multiple testing correction for ND (P=0.033). Rs2236196 was associated with cigarettes per day (P=0.003), with similar association patterns observed in both ancestry groups.

Nested case-control study of 1,673 Caucasian women examining 15 SNPs in pigmentation genes. TYR Arg402Gln (rs1126809) and SLC45A2 Phe374Leu (rs16891982) were significantly associated with skin color and tanning ability. ASIP haplotype (rs4911414[T], rs1015362[G]) increased melanoma risk (OR 1.68) and SCC risk (OR 1.54), while TYRP1 rs1408799 and SLC45A2 -1721 C>G (rs13289) showed protective effects against melanoma (OR 0.77, 0.75 respectively). No associations remained significant after Bonferroni correction.

Genome-wide association studies and comparative genomics have identified major pigmentation loci (SLC24A5, SLC45A2, TYR, OCA2, MC1R, IRF4, TPCN2) showing evidence of strong natural selection in human populations. Light skin variants in Europeans and Asians underwent complete or near-complete selective sweeps, with SLC24A5 rs1426654 and SLC45A2 variants representing independent evolutionary mechanisms. Critical skin-lightening variants arose 11,000-30,000 years ago during human demographic expansion, driven by UV radiation exposure, vitamin D synthesis requirements, and possibly sexual selection.

A cross-sectional genetic association study examining 362 Danish individuals investigating relationships between pigmentation genes and quantitative skin color, nevus counts, and familial atypical multiple-mole and melanoma (FAMMM) syndrome. MC1R variants were significantly associated with lighter arm pigmentation (p < 0.001), indicating effects on tanning response rather than constitutive skin color. No significant associations with FAMMM or nevus counts remained significant after Bonferroni correction for multiple testing.

This Danish study of 246 healthy individuals and 116 at-risk melanoma patients investigated associations between 32 pigmentary SNPs and quantitative skin color, nevi count, and familial atypical multiple-mole and melanoma (FAMMM) syndrome. Individuals carrying two or more MC1R variants (including missense mutations p.TYR152* and frameshift p.Asn29Glnfs*14) had significantly lighter skin on the upper-inner arm (p<0.001) reflecting impaired tanning ability, but no associations were found with FAMMM syndrome, suggesting FAMMM genetics are distinct from pigmentation pathways.

This study investigates allele frequencies of two coding SNPs in pigmentation genes SLC24A5 (p.A111T, rs1426654) and SLC45A2 (p.L374F, rs16891982) across multiple human populations including Chinese, Uygurs, Ghanaians, South African Xhosa, South African Europeans, and Sri Lankans. The derived 111T allele of SLC24A5 and 374F allele of SLC45A2 are nearly fixed in Europeans but absent or rare in other populations, confirming their utility as ancestry informative markers (AIMs). The study demonstrates that SLC45A2 is a more specific AIM than SLC24A5, particularly for distinguishing Sri Lankans from Europeans, and provides evidence for directional selection acting on these genes in European populations.