CC BY 4.0 · Glob Med Genet 2023; 10(03): 190-193
DOI: 10.1055/s-0043-1771184
Case Report

Molecular Evaluation of Joubert Syndrome and Hearing Impairment in a Patient with Ataxic Cerebral Palsy

N. Sreedevi
1   Department of Speech-Language Sciences, All India Institute of Speech and Hearing, Mysore, India
N. Swapna
2   Department of Speech-Language Pathology, All India Institute of Speech and Hearing, Mysore, India
Santosh Maruthy
1   Department of Speech-Language Sciences, All India Institute of Speech and Hearing, Mysore, India
T. Jayakumar
1   Department of Speech-Language Sciences, All India Institute of Speech and Hearing, Mysore, India
3   Unit for Human Genetics, All India Institute of Speech and Hearing, Mysore, India
› Author Affiliations
Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.


Joubert syndrome (JBTS) is a rare autosomal recessive or X-linked congenital brain malformation with strong genetic heterogeneity. Other neurological features of JBTS include hypotonia, ataxia, developmental delay, and cognitive impairment. Hearing loss with JBTS has been reported in the literature. We present the case of a 3.5-year-old boy born to a healthy consanguineous South Indian couple who was presented with ataxic cerebral palsy (CP) and hearing impairment; medical reports confirmed typical brain malformations of JBTS. Hearing impairment was screened by audiological assessment, which confirmed the presence of severe-profound hearing loss with outer hair cell dysfunction. Whole-exome sequencing (WES) was performed to know the molecular aspects of the condition and to detect any novel mutations. The homozygous mutation AHI1 c.2023G > A associated with JBTS type 3 and GJB2 c.71G > A mutation associated with hearing impairment were identified. Sanger sequencing was performed to validate the result and it identified heterozygous AHI1 c.2023G > A and GJB2 c.71G > A in the patient's parents. This study confirms the diagnosis of JBTS by WES helps identify the genetic causes of hereditary disorders that accelerate genetic evaluation and counseling for at-risk families.

Ethical Approval

The study was approved by the Ethics Committee of All India Institute of Speech and Hearing, Mysore, India.

Author Contribution

N. Sreedevi was responsible for conceptualization, supervision, and project administration. N Swapna contributed to conceptualization. Santosh Maruthy was responsible for supervision and project administration. T. Jayakumar contributed to supervision. Charles Sylvester was responsible for the methodology, molecular biology, bioinformatics, and writing the original manuscript.

Publication History

Received: 12 May 2023

Accepted: 20 June 2023

Article published online:
17 July 2023

© 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (

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