Chromatin assembly factor subunit CHAF1A as a monogenic cause for oculo-auriculo-vertebral spectrum.

Area of Science:

• Genetics
• Developmental Biology
• Human Malformations

Background:

• Oculo-auriculo-vertebral spectrum (OAVS) involves abnormal development of the first and second branchial arches.
• While not considered purely monogenic, specific genes have been implicated in a small subset of OAVS cases.

Purpose of the Study:

• To investigate the genetic basis of Oculo-auriculo-vertebral spectrum (OAVS).
• To identify novel genetic variants associated with OAVS and related developmental abnormalities.

Main Methods:

• Genetic analysis of individuals diagnosed with Oculo-auriculo-vertebral spectrum (OAVS).
• Identification and characterization of heterozygous loss-of-function variants in the CHAF1A gene.

Main Results:

• Heterozygous, likely loss-of-function variants in the CHAF1A gene were identified in 8 individuals with OAVS.
• Affected individuals exhibited characteristic OAVS features, including ear and mandibular asymmetry, preauricular tags, and vertebral malformations.
• Kidney malformations were also observed in two patients.

Conclusions:

• The findings implicate CHAF1A, a component of chromatin assembly factor-1 (CAF-1), in the etiology of OAVS.
• Dysregulation of CHAF1A supports the hypothesis that disruptions in early developmental gene regulation contribute to OAVS and Recurrent Constellations of Embryonic Malformations (RCEM).