Inverted duplication deletion chromosome 8p23.1

Yang et al. “Prenatal diagnosis and molecular cytogenetic characterization of 12 cases of chromosome 8 inverted duplication deletion syndrome”. “Orphanet Journal of Rare Diseases,” 2025, v. 20:421.

Inverted duplication deletion of the short arm, p, of chromosome 8 is a rare chromosomal rearrangement that involves a deletion of the 8p23.1-pter region and an inverted duplication of 8p23.1 to the centromere region of variable size. There are over 100 cases published in literature to-date. Individuals with chromosome 8p inverted duplication deletion are characterized by intellectual disability, facial dysmorphic features, central nervous system anomalies, congenital heart defects, and hypotonia. Prenatal cases have also highlighted ultrasound findings such as hydrocephalus, cerebellar hypoplasia, agenesis or dysplasia of the corpus callosum, ventriculomegaly, congenital heart disease, hydronephrosis, dysmorphic facial features, and limb deformities. Overall, the prenatal diagnosis of 8p inverted duplication deletion is complex and variable, making it difficult to convey to parents. Thus, Yang et al. conducted a retrospective review of prenatal genetic diagnoses in China and identified 12 cases of chromosome 8p inverted duplication deletion. Of these 12 cases, 11 chose to voluntarily terminate the pregnancy.

The one case that resulted in continued pregnancy and delivery was identified to have a paternally inherited 4.5 Mb deletion at 8p23.2p23.1 and an 8.2 Mb inverted duplication at 8p23.1p21.3. The pregnancy was notable for left lateral cerebral ventricle being slightly enlarged. At 5-years-old, the female proband showed no apparent abnormalities and was attending regular kindergarten. Her father had the same inv dup del 8p as his daughter. Her father is in sales-related work, whose highest level of education is high school. Notably, the living female and her father had the smallest duplicated region amongst the 12 cases. The other cases had duplication sizes ranging from 17.2 to 33 Mb. Though, no candidate genes have been identified in the duplicated region. However, the authors hypothesize that the genes DLGAP2, CLN8, and ARHGEF10 in the 2.4 Mb telomeric region are candidate genes for the deletion, while GATA4 and SOX7 are key genes in the 8p23.1 region. The current paper reinforces how length of the duplication is clinically correlated with the severity of the condition.

Chromosome Disorder Outreach Inc. medical geneticist and medical advisor Dr. Iosif Lurie M.D. Ph.D examines newly published research studies to locate the most important and relevant for our members. Synopses of these articles are then posted to our website’s research pages. Review and formatting by Nicole Talaba, MS CGC. For more information on any article please contact info@chromodisorder.org