Background <p>Mohr–Tranebjærg syndrome (MTS) is a rare X-linked recessive neurodegenerative disorder, typically presenting with progressive sensorineural hearing loss in early childhood, followed by neurological deterioration, dystonia, ataxia, and visual impairment.</p> Objective <p>This study aimed to conduct a comprehensive clinical, genetic, and phenotypic review of MTS, with particular emphasis on mutations in the <i>TIMM8A</i> gene and contiguous deletions involving Bruton tyrosine kinase (<i>BTK</i>), which give rise to an extended phenotype known as XLA-MTS.</p> Methods <p>A systematic literature review was performed between February 1995 and May 2025 using PubMed, Embase, and Scopus databases. Clinical and genetic data from 75 individual patients with molecularly confirmed MTS or XLA-MTS were extracted and stratified into two groups: classical MTS (<i>TIMM8A</i> mutations only, <i>n</i> = 51) and XLA-MTS (contiguous deletions of <i>TIMM8A</i> and <i>BTK</i>, <i>n</i> = 24). Key clinical features were compared using Fisher’s exact test and Student’s t-test.</p> Results <p>Immunodeficiency with agammaglobulinemia (XLA) was present in 100% of XLA-MTS cases (24/24) versus 0% of classical MTS cases (0/51). Delayed language development (DLD) was significantly more frequent in XLA-MTS (52,4%, 13/24) than in classical MTS (19.6%, 10/51) <i>(p</i> = 0.004). In contrast, progressive cortical blindness (PCB) was markedly more common in classical MTS (58,8%, 30/51) than in XLA-MTS (12,3%, 3/24) (<i>p</i> &lt; 0.001).</p> Conclusions <p>Contiguous deletions encompassing <i>TIMM8A</i> and <i>BTK</i> define a distinct clinical-genetic entity—XLA-MTS—characterized by the triad of early-onset deafness, neurodevelopmental delay, and immunodeficiency. These findings underscore the critical need for expanded genetic testing beyond <i>TIMM8A</i> alone to ensure accurate diagnosis, prognostic stratification, and appropriate clinical management, particularly in patients with syndromic deafness and developmental delay.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

XLA-MTS: a distinct clinical genetic entity characterized by immunodeficiency and neurodevelopmental delay

  • Ignacio Ventura,
  • Francisco Revert-Ros,
  • Fernando Revert,
  • Juan Carlos Marín-Paya,
  • Natalia Ruíz-Pérez,
  • Jesús Ángel Prieto-Ruiz,
  • José Miguel Hernández-Andreu

摘要

Background

Mohr–Tranebjærg syndrome (MTS) is a rare X-linked recessive neurodegenerative disorder, typically presenting with progressive sensorineural hearing loss in early childhood, followed by neurological deterioration, dystonia, ataxia, and visual impairment.

Objective

This study aimed to conduct a comprehensive clinical, genetic, and phenotypic review of MTS, with particular emphasis on mutations in the TIMM8A gene and contiguous deletions involving Bruton tyrosine kinase (BTK), which give rise to an extended phenotype known as XLA-MTS.

Methods

A systematic literature review was performed between February 1995 and May 2025 using PubMed, Embase, and Scopus databases. Clinical and genetic data from 75 individual patients with molecularly confirmed MTS or XLA-MTS were extracted and stratified into two groups: classical MTS (TIMM8A mutations only, n = 51) and XLA-MTS (contiguous deletions of TIMM8A and BTK, n = 24). Key clinical features were compared using Fisher’s exact test and Student’s t-test.

Results

Immunodeficiency with agammaglobulinemia (XLA) was present in 100% of XLA-MTS cases (24/24) versus 0% of classical MTS cases (0/51). Delayed language development (DLD) was significantly more frequent in XLA-MTS (52,4%, 13/24) than in classical MTS (19.6%, 10/51) (p = 0.004). In contrast, progressive cortical blindness (PCB) was markedly more common in classical MTS (58,8%, 30/51) than in XLA-MTS (12,3%, 3/24) (p < 0.001).

Conclusions

Contiguous deletions encompassing TIMM8A and BTK define a distinct clinical-genetic entity—XLA-MTS—characterized by the triad of early-onset deafness, neurodevelopmental delay, and immunodeficiency. These findings underscore the critical need for expanded genetic testing beyond TIMM8A alone to ensure accurate diagnosis, prognostic stratification, and appropriate clinical management, particularly in patients with syndromic deafness and developmental delay.