Non-Mendelian inheritance

<p>Non-Mendelian inheritance is any pattern  in which traits do not segregate in accordance with <a href="/facts/Mendelian_inheritance/v2038wkl">Mendel's laws</a>. These laws describe the inheritance of traits linked to single <a href="/facts/Gene/e1swwPY6">genes</a> on <a href="/facts/Chromosome/FRGf11FC">chromosomes</a> in the nucleus. In <a href="/facts/Mendelian_inheritance/v2038wkl">Mendelian inheritance</a>, each parent contributes one of two possible <a href="/facts/Allele/8FxCS9KA">alleles</a> for a trait. If the <a href="/facts/Genotype/MlzK1Mfz">genotypes</a> of both parents in a genetic cross are known, Mendel's laws can be used to determine the distribution of <a href="/facts/Phenotype/vxWXKGLj">phenotypes</a> expected for the population of offspring.  There are several situations in which the proportions of phenotypes observed in the progeny do not match the predicted values.
</p><p>Certain inherited diseases and their presentation display non-Mendelian patterns, complicating making predictions from family history.
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Non-Mendelian inheritance open-in-new

Non-Mendelian inheritance