Coexistence of urogenital malformations in a female fetus with de novo 15q24 microdeletion and a literature review

Abstract

Background: 15q24 microdeletion is a relatively new syndrome caused by nonallelic homologous recombination (NAHR) between low-copy repeats (LCRs) in the 15q24 chromosome region. This syndrome is characterized by a spectrum of clinical symptoms including global developmental delay, intellectual disability, facial dysmorphisms, and congenital malformations of the extremities, eye, gastrointestinal tract, genitourinary system, and genitalia.

Method: Molecular cytogenetic analysis was performed using whole genome single-nucleotide polymorphism (SNP) microarray analysis. Autopsy examination including gross and microscopic examination were performed. In addition, a thorough review of the literature on 15q24 microdeletion was completed and summarized in table format.

Result: Molecular cytogenetic analysis revealed a 3.88 MB interstitial deletion within 15q24.1 to 15q24.3 (74,353,735-78,228,485 bp) in our case. Autopsy examination showed congenital malformations within the genitourinary system and genitalia, including left kidney agenesis and uterus didelphys. After thorough literature review, we found a series of midline defects associated with 15q24 microdeletion syndrome.

Conclusion: We report the first case of coexistence of urogenital abnormalities, including left kidney agenesis and uterus didelphys, with 15q24 microdeletion syndrome, which is also associated with midline defects secondary to abnormal development. Since 15q24 microdeletion syndrome is a relatively new entity, fully characterizing its variation and severity requires additional examination of the genetics, molecular profile and structural and functional abnormalities in affected patients. Due to the limited data in the literature, statistical analysis of abnormalities in each organ system is not possible. However, we can predict that novel genetic pathways involving cell migration, adhesion, apoptosis, and embryo development might be discovered with the advanced study of 15q24 microdeletion syndrome.

Keywords: 15q24 microdeletion; intrauterine growth restriction (IUGR); kidney agenesis; uterus didelphys.