Binder phenotype: associated findings and etiologic mechanisms

Area of Science:

• Medical Genetics
• Developmental Biology
• Craniofacial Abnormalities

Background:

• Binder phenotype (BP), also known as maxillonasal dysostosis, is characterized by a distinct set of facial malformations.
• Understanding the etiology and developmental mechanisms of BP is crucial for diagnosis and management.

Observation:

• This study reviewed 8 patients diagnosed with BP, identifying associated malformations and genetic diagnoses.
• Cases were ascertained through a population-based registry, providing a potentially more accurate incidence of BP (approximately 1 in 18,000).
• Chromosome analysis in initial cases revealed trisomy 21, trisomy 18, and mosaic trisomy 18.

Findings:

• Among 8 patients meeting BP criteria, diagnoses included vitamin K epoxide reductase deficiency, Xp22.3 deletion with chondrodysplasia punctata, Stickler syndrome, fetal warfarin syndrome, Robinow syndrome, and unknown etiology.
• Excluding chromosomal syndromes, 3 of the remaining 8 cases shared involvement of the vitamin K-dependent metabolic pathway.
• This suggests a significant pathogenetic role for the vitamin K pathway in the development of BP.

Implications:

• The findings highlight that chromosomal, genetic, and exogenous factors can contribute to BP.
• The vitamin K metabolic pathway emerges as a potential key mechanism in BP development.
• Further clinical characterization of BP cases can enhance understanding of its diverse causative developmental pathways.