SLC45A2 rs28777: Understanding Your Pigmentation Genetics
The rs28777 variant is a single nucleotide polymorphism located within the SLC45A2 gene. It has been statistically associated with variations in human skin reflectance, hair color, and tanning response.
What each genotype means
Typical baseline pigmentation tendency
You carry two copies of the ancestral A allele at rs28777 in the SLC45A2 gene. In population genetic studies, this genotype is generally correlated with standard baseline skin reflectance and melanin synthesis. Because rs28777 is a synonymous marker often linked to other pigmentation variants, its standalone effect is modest.
Carried by approximately 50% to 55% of individuals of European descent, and predominant in African and Asian ancestries.
Intermediate pigmentation association
You carry one copy of the C variant allele and one ancestral A allele. Studies investigating the SLC45A2 locus report that carrying a single C allele is modestly associated with variations in skin tone reflectance and tanning response. Evidence for this specific synonymous marker acting independently is limited, as it frequently co-occurs with other regulatory and coding variants across the locus.
Found in approximately 40% of European populations, but less common in individuals of non-European ancestry.
Altered skin reflectance association
You carry two copies of the C variant allele at rs28777 in SLC45A2. Published research observes that homozygous C carriers tend to show statistical associations with lighter skin reflectance and subtle differences in tanning behavior. However, this is a non-coding synonymous variant with limited direct functional evidence, and overall pigmentation is governed by complex polygenic networks.
Present in roughly 8% of individuals of European ancestry, and rare in most African and East Asian populations.
What is the rs28777 Variant?
The rs28777 variant is a specific genetic marker, or single nucleotide polymorphism (SNP), found within the SLC45A2 gene. In genetics, a SNP represents a variation at a single position in the DNA sequence among individuals. The rs28777 variant involves a substitution where either an adenine (A) or a cytosine (C) base is present at a specific location on chromosome 5. This variant is categorized as a synonymous marker, meaning that while it sits within the gene, it does not necessarily change the amino acid sequence of the protein produced by the gene. Instead, researchers study such markers because they often serve as signposts for nearby genetic variations that may influence physical traits. Because it is located in a region of the genome involved in pigmentation, it has been a subject of interest in studies exploring the genetic basis of human physical diversity.
The Role of the SLC45A2 Gene
The SLC45A2 gene, also known as MATP, provides the genetic blueprint for a transporter protein located in melanocytes. Melanocytes are specialized cells responsible for producing melanin, the pigment that determines the color of human skin, hair, and eyes. The protein encoded by SLC45A2 is thought to be essential for the proper function of melanosomes, which are the internal structures within melanocytes where melanin synthesis occurs. By facilitating the transport of molecules necessary for this process, the SLC45A2 protein plays a direct role in regulating the amount and type of pigment produced. Mutations in this gene are known to cause oculocutaneous albinism type 4, a condition characterized by significantly reduced pigmentation. In the general population, common variations in this gene are associated with the natural spectrum of human pigmentation, contributing to the wide variety of skin and hair colors observed globally.
Research and Statistical Associations
Scientific research, including genome-wide association studies (GWAS), has identified rs28777 as being associated with several pigmentation-related traits. Specifically, studies have linked this variant to differences in skin reflectance, hair color, and the ability of the skin to tan when exposed to ultraviolet light. While these statistical associations are documented in scientific literature, the evidence strength is considered limited in terms of clinical application. It is important to understand that these findings describe population-level trends rather than individual predictions. Many factors, including other genetic variants and environmental influences, contribute to an individual's physical appearance. Because pigmentation is a complex trait influenced by numerous genes, the presence of a specific genotype at rs28777 does not determine a person's phenotype in isolation. Researchers continue to investigate how this and other variants interact to shape human traits.
Interpreting Your Genetic Information
When reviewing information about variants like rs28777, it is essential to maintain a clear perspective on what this data means. Genetic associations are tools for scientific discovery, helping researchers understand the biological pathways that influence human development and physical traits. However, this information is not a diagnostic tool and cannot be used to predict an individual's health outcomes or specific physical characteristics with certainty. You cannot change your genetic code, and having a particular genotype at this locus is simply a reflection of natural human genetic variation. If you have questions about your skin health, such as concerns regarding sun sensitivity or changes in skin appearance, the most appropriate course of action is to consult with a dermatologist or a qualified healthcare professional. They can provide personalized advice based on your medical history and clinical examination, which are far more informative than any single genetic marker.
How common is this variant?
The rs28777 variant is relatively common, with a minor allele frequency of approximately 0.28 in European populations.
Frequently asked questions
Is rs28777 a cause of skin cancer?
No, rs28777 is not a cause of skin cancer. While it is associated with pigmentation traits like tanning response, it is not a diagnostic marker for disease risk.
Can I use this SNP to predict my hair color?
No, you cannot use this SNP to predict your hair color. Pigmentation is a complex trait influenced by many different genes and environmental factors, not just a single variant.
What should I do if I have the 'C' allele?
The presence of a specific allele at this location is a normal part of human genetic variation. No action is required, as this is not a medical finding.
Where can I find more information on SLC45A2?
You can find reliable information about the SLC45A2 gene through resources like MedlinePlus Genetics or the NCBI Gene database. These sites provide detailed summaries of gene function and associated research.
Sources & further reading
Educational information only, last refreshed 10/10/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This synonymous variant is in high linkage disequilibrium with functional alleles that influence human skin, hair, and eye pigmentation.
This missense variant (p.Phe374Leu) is a major determinant of human skin, hair, and eye pigmentation, showing strong evidence of selection in European populations.
This missense variant (p.Phe374Leu) is a key ancestry-informative marker and a classic signature of recent positive selection, strongly associated with skin pigmentation and melanoma risk.
This variant (p.Phe374Leu) is strongly associated with lighter skin, hair, and eye pigmentation, as well as an increased sensitivity to UV-induced skin damage.
The p.Phe374Leu variant in SLC45A2 is a major determinant of human pigmentation variation, influencing skin, hair, and eye color across global populations.
Promoter-associated regulatory variant implicated in hair and skin pigmentation variation across human populations.