by Research Society on Alcohol. Retrieved from https://medicalxpress.com/news/2026-08-rare-chromosomal-differences-children-fetal.html
One in four children diagnosed with fetal alcohol spectrum disorder was found to have rare chromosomal differences at considerably higher rates than the general population, according to a study published in Alcohol: Clinical and Experimental Research. Half of those differences were associated with harmful or potentially harmful genetic variations. The study’s authors recommend high-resolution genetic testing whenever fetal alcohol spectrum disorder is diagnosed to provide a more complete clinical diagnosis and identify opportunities for improved medical management.
Prenatal alcohol exposure can, but does not always, lead to fetal alcohol spectrum disorder, a lifelong condition marked by severe neurodevelopmental impairment and other differences. Prior research suggests that certain factors, including genetic factors, may increase or decrease susceptibility to developing fetal alcohol spectrum disorder. Chromosomal variations in sections of DNA called CNVs, or copy number variants, contribute to this susceptibility. However, the mechanism by which alcohol exposure influences or interacts with neurodevelopmental genes is not well understood.
Researchers conducted a retrospective review of all 175 Australian children diagnosed with fetal alcohol spectrum disorder at a single clinic from 2015 to 2022 to identify rare CNVs using a specific genetic test called chromosomal microarray analysis.
They found rare CNVs in a quarter of the cases, and half of those CNVs contained genes that were pathogenic or potentially pathogenic. For example, some of the rare CNVs identified play a role in central nervous system function and physical, developmental and immune system problems. By comparison, rare CNVs are found in only 10% of the general population and in up to 15% of children with other developmental or congenital differences.