Acne Knowledge of Hispanic Parents of Teenagers with Mild to Moderate Acne.

We performed a cross-sectional study of Hispanic and non-Hispanic parents of children with acne using a survey designed to determine their level of awareness of acne and its treatment; 82% of Hispanic parents and 40% of non-Hispanic parents agreed that a health care provider should treat mild acne (p < 0.001). Hispanic parents of adolescents with acne agreed more frequently than non-Hispanic parents that children with mild and moderate acne should be taken to a health care provider for treatment, but they tended not to visit health care providers. Future studies should aim to determine the reasons for this discrepancy, after which culturally sensitive educational programs can be developed to address this disparity.

Epistatic and combinatorial effects of pigmentary gene mutations in the domestic pigeon.

Understanding the molecular basis of phenotypic diversity is a critical challenge in biology, yet we know little about the mechanistic effects of different mutations and epistatic relationships among loci that contribute to complex traits. Pigmentation genetics offers a powerful model for identifying mutations underlying diversity and for determining how additional complexity emerges from interactions among loci. Centuries of artificial selection in domestic rock pigeons (Columba livia) have cultivated tremendous variation in plumage pigmentation through the combined effects of dozens of loci. The dominance and epistatic hierarchies of key loci governing this diversity are known through classical genetic studies, but their molecular identities and the mechanisms of their genetic interactions remain unknown. Here we identify protein-coding and cis-regulatory mutations in Tyrp1, Sox10, and Slc45a2 that underlie classical color phenotypes of pigeons and present a mechanistic explanation of their dominance and epistatic relationships. We also find unanticipated allelic heterogeneity at Tyrp1 and Sox10, indicating that color variants evolved repeatedly though mutations in the same genes. These results demonstrate how a spectrum of coding and regulatory mutations in a small number of genes can interact to generate substantial phenotypic diversity in a classic Darwinian model of evolution.