Genetic Origin of Variation in Human Skin Color
This activity guides the analysis of a published scientific figure from a study that investigated a gene involved in determining human skin color.
This study focused on the gene SLC24A5, which codes for a protein involved in melanin production. Variations in this gene are associated with variations in human skin pigmentation. The scientists considered two alleles of SLC24A5: an ancestral allele “G” and a derived allele “A.” The figure shows the different distributions in human skin pigmentation (melanin index) for three SLC24A5 genotypes (GG, AG, and AA), relative to a regression line calculated for the GG genotype.
The “Educator Materials” document includes a captioned figure, background information, graph interpretation, and discussion questions. The “Student Handout” includes a captioned figure and background information.
Student Learning Targets
- Analyze and interpret data from a scientific figure.
- Describe how variations in genotype contribute to variations in phenotype.
allele, genotype, histogram, melanin, melanosome, pigmentation, single nucleotide polymorphism (SNP), zebrafish
Lamason R. L., Manzoor-Ali P. K. Mohideen, Jason R. Mest, Andrew C. Wong, Heather L. Norton, Michele C. Aros, Michael J. Jurynec, et al. “SLC24A5, a putative cation exchanger, affects pigmentation in zebrafish and humans.” Science 310, 5755 (2005): 1782–1786. https://doi.org/10.1126/science.1116238.
HS-LS3-1, HS-LS4-4; SEP2, SEP4, SEP5
1.B.1, 4.C.1; SP1, SP2, SP5
Math.S-ID.3, Math.S-IC.1; MP2, MP5
CC3; DP2, DP3