Braddock-Carey syndrome: A 21q22 contiguous gene syndrome encompassing RUNX1

Area of Science:

• Genetics
• Developmental Biology
• Pediatrics

Background:

• Braddock-Carey syndrome, first described in 1994, presents with Pierre Robin sequence, neonatal thrombocytopenia, agenesis of the corpus callosum, distinct facial features, enamel hypoplasia, and severe developmental delay.
• Subsequent reports identified similar phenotypes in patients with deletions in the 21q22 region, a critical area for Down syndrome.

Observation:

• Reinvestigation of the original Braddock-Carey syndrome patients revealed a shared genetic etiology with cases involving 21q22 deletions.
• Clinical similarities between Braddock-Carey syndrome and previously reported 21q22 deletion cases prompted a genetic re-evaluation.

Findings:

• This study provides evidence that Braddock-Carey syndrome is a contiguous gene deletion syndrome.
• The specific genetic cause identified is a deletion involving the 21q22 region, including the RUNX1 gene.

Implications:

• This discovery reclassifies Braddock-Carey syndrome and related disorders as a distinct contiguous gene deletion syndrome.
• Understanding the role of RUNX1 in this syndrome opens avenues for future research into "Fanconi-like" conditions and developmental abnormalities.