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Open Access 01-12-2024 | Disorders of Intellectual Development | Case report

De novo KAT6B mutation causes Say–Barber–Biesecker–Young–Simpson variant of Ohdo syndrome in an Iranian boy: a case report

Authors: Behzad Davarnia, Mohammad Panahi, Bahareh Rahimi, Hassan Anari, Reza Farajollahi, Ehsan Abbaspour Rodbaneh, Farhad Jeddi

Published in: Journal of Medical Case Reports | Issue 1/2024

Abstract

Background

Say–Barber–Biesecker–Young–Simpson (SBBYS) (OMIM #603736, Ohdo syndrome variant) is a rare type of severe blepharophimosis intellectual disability syndrome, which is generally characterized by a global developmental delay, distinctive facial features, and intellectual disability with multiple congenital anomalies, including skeletal involvement, missing, or underdeveloped kneecaps, and genital anomalies, in affected males. It has been shown that mutations in the KAT6B gene, which is a lysine acetyltransferase-encoding gene, have been associated with SBBYS syndrome. All the known variants are dominant de novo mutations that result in protein truncation.

Case presentation

A 14-year-old Iranian Azeri boy with an intellectual disability, distinct dysmorphic facial features such as open-mouth expression, sparse medial eyebrows, widely spaced upward-slanted eyes, epicanthal folds, broad nasal bridge, low-set ears, anteverted ears, short philtrum, hypertelorism, microphthalmia is presented in this case study. Cryptorchidism was reported. Neurologically, the patient presented with poor eye contact, hypotonia, and speech difficulties. In the skeletal X-ray, underdeveloped kneecaps with some new features were observed.

Conclusion

We present the first case of SBBYS syndrome in association with some new anomaly features in the Iranian population. Based on this diagnosis, we could provide the patient with a suitable plan of management as well as appropriate genetic counseling for his family.

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Title: De novo KAT6B mutation causes Say–Barber–Biesecker–Young–Simpson variant of Ohdo syndrome in an Iranian boy: a case report
Authors: Behzad Davarnia
Mohammad Panahi
Bahareh Rahimi
Hassan Anari
Reza Farajollahi
Ehsan Abbaspour Rodbaneh
Farhad Jeddi
Publication date: 01-12-2024
Publisher: BioMed Central
Keywords: Disorders of Intellectual Development
Intellectual Disability
Published in: Journal of Medical Case Reports / Issue 1/2024
Electronic ISSN: 1752-1947
DOI: https://doi.org/10.1186/s13256-023-04237-w

Keynote webinar | Spotlight on medication adherence

Springer Medicine

De novo KAT6B mutation causes Say–Barber–Biesecker–Young–Simpson variant of Ohdo syndrome in an Iranian boy: a case report

Abstract

Background

Case presentation

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Case presentation

Conclusion

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