USH2A mutation analysis in 70 Dutch families with Usher syndrome type II.

Usher syndrome type II (USH2) is characterised by moderate to severe high-frequency hearing impairment, progressive visual loss due to retinitis pigmentosa and intact vestibular responses. Three loci are known for USH2, however, only the gene for USH2a (USH2A) has been identified. Mutation analysis of USH2A was performed in 70 Dutch USH2 families.

Evaluation of visual impairment in Usher syndrome 1b and Usher syndrome 2a.

Purpose: To evaluate visual impairment in Usher syndrome 1b (USH1b) and Usher syndrome 2a (USH2a).

Methods: We carried out a retrospective study of 19 USH1b patients and 40 USH2a patients. Cross-sectional regression analyses of the functional acuity score (FAS), functional field score (FFS) and functional vision score (FVS) related to age were performed.

Pure tone hearing thresholds and speech recognition scores in Dutch patients carrying mutations in the USH2A gene.

Objective: To establish the audiometric profile and speech recognition characteristics in 36 Usher IIa patients, carrying one (A) or two (B) pathogenic mutations in the gene.

Study Design: Family study.

Setting: Tertiary referral center.