Use of array comparative genome hybridization in orofacial clefting

Area of Science:

• Genetics
• Developmental Biology
• Medical Diagnostics

Background:

• Orofacial clefting affects 1 in 700-1000 births, with some cases linked to genetic mutations.
• Recognizable syndromes with clefts have specific genetic tests, but many patients with anomalies lack a diagnosis.
• Chromosome analysis is a traditional genetic test for undiagnosed clefting cases.

Observation:

• A 7-month-old infant presented with cleft palate, developmental delay, and family history of velopharyngeal insufficiency.
• Standard chromosome analysis did not reveal a genetic cause for the infant's condition.
• Array comparative genome hybridization (aCGH) identified a microdeletion on chromosome 7p, also present in the infant's mother.

Findings:

• aCGH successfully identified a sub-microscopic deletion on chromosome 7p in a patient with cleft palate and developmental delay.
• This deletion was missed by conventional chromosome analysis.
• The identified deletion was also present in the affected infant's mother, suggesting a familial link.

Implications:

• aCGH is a valuable diagnostic tool for identifying genetic causes of orofacial clefting when standard tests fail.
• This technology aids in diagnosing patients with complex anomalies not fitting recognizable syndromes.
• Consideration of aCGH is recommended for suspected genetic etiologies of clefting, even with normal cytogenetic results.