haploinsufficiency

Full Definition

Haploinsufficiency occurs when a single functional copy of a gene cannot provide adequate gene product for normal cellular function, resulting in a genetic disorder. This mechanism is common in many genetic conditions where heterozygous loss-of-function mutations cause disease. Examples include Turner syndrome (X chromosome haploinsufficiency) and many contiguous gene deletion syndromes. Understanding haploinsufficiency is crucial for interpreting genetic test results and providing accurate genetic counseling about inheritance risks and reproductive options.

Usage

Usage note: One word; stress on the fourth syllable.

In Context

• "The deletion resulted in haploinsufficiency of the critical developmental gene." — Genetic test interpretation
• "Haploinsufficiency explains the autosomal dominant inheritance pattern observed." — Genetic counseling documentation