Maternally inherited autosomal dominant intellectual disability caused by 16p13.3 microduplication

Area of Science:

• Genetics
• Human Genetics
• Medical Genetics

Background:

• 16p13.3 duplication syndrome is recognized as a reciprocal microduplication of Rubinstein-Taybi syndrome.
• The CREBBP gene is considered the dosage-sensitive critical gene for this reciprocal duplication and deletion syndrome.
• Previously reported cases have been de novo.

Observation:

• A rare case of a 1-megabase duplication on 16p13.3 was identified via SNP array testing.
• The duplication was maternally inherited.
• The patient presented with moderate intellectual disability, normal growth, and characteristic facial features.

Findings:

• The patient's mother exhibited mild intellectual disability, normal growth, camptodactyly, proximally implanted thumbs, and distinctive facial features.
• This case demonstrates maternal inheritance of the 16p13.3 duplication syndrome.
• Phenotypic variability is observed, with affected mother and child showing overlapping yet distinct features.

Implications:

• This report expands the understanding of 16p13.3 duplication syndrome.
• It highlights the possibility of non-de novo inheritance patterns.
• Further delineation of the syndrome's clinical spectrum and genetic basis is provided.