The following is a summary of “Expanding the Phenotype of 8p23.1 Deletion Syndrome: Eight New Cases Resembling the Clinical Spectrum of 22q11.2 Microdeletion,” published in the JANUARY 2023 issue of Pediatrics by Montenegro, et al.

About 8 individuals with 8p23.1DS with clinical characteristics that overlap the phenotypic spectrum of 22q11.2DS are presented to demonstrate the value of early molecular diagnosis in the clinical management of uncommon disorders.

For a study, researchers intended to give an early molecular diagnosis of the 22q11.2 deletion syndrome in 118 newborns with congenital cardiac disease. The SALSA multiplex ligation-dependent probe amplification (MLPA) probemix kits P064-B2, P036-E1, P070-B2, P356-A1, and P250-B1 were used on patients to do comparative genomic screening to validate the clinical diagnosis. The patients next underwent a genomic microarray utilizing the Infinium CytoSNP-850K BeadChip to validate the loss, pinpoint its breakpoints, and look for genomic copy number variants.

The 8p23.1 typical loss affecting the PPP1R3B, MSRA, and GATA4 genes was discovered in the 5 patients by MLPA using 3 separate kits. In addition, a detailed description of the breakpoints and the exclusion of other genetic anomalies were made possible by the array analysis, which was carried out on these 5 patients and 3 more patients (8 patients) who also had clinical suspicion of a 22q11 deletion (8 patients).

To establish a differential diagnosis and rule out the existence of any associated disorders, cytogenomic screening proved effective. The 8p23.1 deletion syndrome presents a complicated clinical picture. However, cytogenomic methods offered a precise diagnosis and aided in deciphering the genotype-phenotype complexity of these individuals. In addition, the studies emphasized the value of early microdeletion syndrome diagnosis and clinical follow-up.

Reference: jpeds.com/article/S0022-3476(22)00787-9/fulltext