Some genes are passed on from parent to offspring without ever being part of a nuclear chromosome. Where are these genes found, and how does this non-nuclear inheritance occur? But why is leaf color ...

In Mendelian inheritance patterns, you receive one version of a gene, called an allele, from each parent. These alleles can be dominant or recessive. Non-Mendelian genetics don’t completely follow ...

You're not an equal product of both parents' genes. Genomic imprinting, a process whereby only one gene copy is expressed, not only exists but, combined with mutations, may lead to disease. In 1965, ...

Retinitis pigmentosa (RP) is an eye condition that can be genetic. In this way, people usually need to inherit two copies of a genetic variation that causes RP, one coming from each parent. RP may ...

Von Willebrand disease (VWD) is a bleeding disorder in which the blood does not clot as it should. Usually, people have VWD due to their genes, which may come from a male or female parent. Blood ...