single-gene Mendelian inheritance

genetics

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July 16, 2026

Quick Summary

Single-gene Mendelian inheritance describes how traits are passed from parents to offspring through discrete units called genes. Formulated by Gregor Mendel, these principles explain that genes, or alleles, separate during sex cell formation and combine randomly in offspring.1

Key concepts include:
* Law of Segregation: Alleles of a gene pair separate, with each sex cell receiving one allele.1
* Law of Independent Assortment: Alleles of different genes sort independently of each other.1
* Dominance: One allele may mask the effect of another. Complete dominance means one allele fully expresses its trait, while incomplete dominance results in an intermediate trait in heterozygotes.12

A Punnett square is a tool used to predict the genotypes and phenotypes of offspring based on Mendelian inheritance. While Mendelian inheritance explains many traits, some single-gene disorders exhibit non-Mendelian patterns.34

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human genetic disease
Diseases associated with single-gene Mendelian inheritance
The term Mendelian is often used to denote patterns of genetic inheritance similar to those described for traits in the garden pea by Gregor Mendel in the 1860s. Disorders associated with single-gene Mendelian inheritance are typically categorized as autosomal dominant, autosomal recessive,…
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The term Mendelian is often used to denote patterns of genetic inheritance similar to those described for traits in the garden pea by Gregor Mendel in the 1860s. Disorders associated with single-gene Mendelian inheritance are typically categorized as autosomal dominant, autosomal recessive,…
Read More