Molecular Characteristics
TAF6 (TATA Box Binding Protein-Associated Factor) gene is located at 7q22.1 and encodes a protein that forms a component of the transcription factor IID complex, which plays an essential role in mediating promoter responses to activators and repressors.
Mutations and pathophysiology
Mutations in TAF6 cause Alazami-Yuan syndrome characterized mainly by intellectual disability, developmental delay, hypotonia, microcephaly, poor speech, and dysmorphic features.
The following are two selected examples of pathologic variants in TAF6:
- Alazami et al. (2015) reported homozygosity for c.212T>C mutation in TAF6 (NM_005641.3) leading to a p.Ile71Thr substitution. The affected patient was born to a consanguineous Saudi family with Alazami-Yuan syndrome.
- Yuan et al. (2015) independently reported the same p.Ile71Thr mutation in three siblings from the same family mentioned by Alazami et al. (2015). Additionally, Yuan et al. (2015) identified a homozygous c.136C>T mutation leading to p.Arg46Cys. The affected patient was born to a consanguineous Turkish family with Alazami-Yuan syndrome.