Pathogenic variants in GJB2 are the most common cause of autosomal recessive sensorineural hearing loss. The classification of c.101T>C/p.Met34Thr and c.109G>A/p.Val37Ile in GJB2 are controversial. Therefore, an expert consensus is required for the interpretation of these two variants.
The ClinGen Hearing Loss Expert Panel collected published data and shared unpublished information from contributing laboratories and clinics regarding the two variants. Functional, computational, allelic, and segregation data were also obtained. Case-control statistical analyses were performed.
The panel reviewed the synthesized information, and classified the p.Met34Thr and p.Val37Ile variants utilizing professional variant interpretation guidelines and professional judgment. We found that p.Met34Thr and p.Val37Ile are significantly overrepresented in hearing loss patients, compared with population controls. Individuals homozygous or compound heterozygous for p.Met34Thr or p.Val37Ile typically manifest mild to moderate hearing loss. Several other types of evidence also support pathogenic roles for these two variants.
Resolving controversies in variant classification requires coordinated effort among a panel of international multi-institutional experts to share data, standardize classification guidelines, review evidence, and reach a consensus. We concluded that p.Met34Thr and p.Val37Ile variants in GJB2 are pathogenic for autosomal recessive nonsyndromic hearing loss with variable expressivity and incomplete penetrance.

OBJECTIVE: This tutorial provides information to aid audiologists in determining when a referral for a genetics evaluation is appropriate for a patient with hearing loss. Direction is given on discussing the benefits and limitations of genetic testing with parents of children with hearing loss.
METHODS: Genetic patterns of inheritance are reviewed, particularly in reference to syndromic and nonsyndromic forms of hearing loss. A review of pertinent literature was performed.
CONCLUSIONS: Audiologists are in a unique position to facilitate investigation into the etiology of a patient\'s hearing loss. This is of high importance in genetic etiologies because the diagnosis can provide information on recurrence risks and other potential health implications. Suggestions are made to help audiologists recognize when a genetics referral is warranted, counsel patients and their parents about the benefits and limitations of genetic testing, and interpret genetic test results.

Cogan\'s syndrome (CS) is a rare chronic inflammatory disorder, classically characterized by interstitial keratitis and sensorineural hearing loss. Recurrent episodes of inner ear disease might result in deafness. In some patients, it may also be accompanied by systemic vasculitis. Diagnosis of CS is often missed or delayed due to its rarity, the nonspecific clinical signs at onset, and the lack of a confirmatory diagnostic test. The mechanisms responsible for CS are unknown; however, in the last decade, the pathogenesis has been somewhat elucidated, suggesting that the disease is a result of inner ear autoimmunity. The autoimmune hypothesis postulates the triggering of the disease by a viral infection via a number of mechanisms, which are mainly as follows: antigenic mimicry, self-perpetuating inflammation by cytokine release, and unveiling hidden epitopes. Aside from its clinical resemblance to other autoimmune disorders, some autoantigen has apparently been identified, namely, CD148 and connexine 26. Treatment should begin as early as possible. While treatment is based primarily on glucocorticoids, there is no standard alternative for patients who respond poorly. Failure of conventional treatment could lead to profound sensorineural hearing loss. From the limited data we have, infliximab seems to be the most promising biological remedy, enabling steroid tapering and leading to improvement in auditory/ocular disease, with better results when administered in early stages. Proposed guidelines for the use of infliximab in CS are found in the last table of the review, in an attempt to define the proper timing for initiating infliximab treatment in order to avoid permanent disability.

暂无摘要。

暂无摘要。