Genetics Home Reference provides consumer-friendly information about the effects of genetic variation on human health.
Health Conditions
Learn about the signs and symptoms, causes, and inheritance of more than 1,200 health conditions with a genetic basis.
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Genes
Find information about the function of more than 1,400 genes and see how changes in these genes are related to health conditions.
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Chromosomes & mtDNA
Read about each of the 23 pairs of human chromosomes and mitochondrial DNA (mtDNA).
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Help Me Understand Genetics
Explore topics in human genetics, from the basics of DNA to genomic research and personalized medicine.
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