NovelTRPM1mutations in two Chinese families with early-onset high myopia, with or without complete congenital stationary night blindness.
OBJECTIVE
To investigate the relationship between high myopia [with or without complete congenital stationary night blindness (CSNB1)] andTRPM1andNYX.


METHODS
Two unrelated families with early-onset high myopia (eoHM) and 96 normal controls were recruited. Sanger sequencing or clone sequencing were used for mutation screening. Further analyses of the available family members and the 96 normal controls were subsequently conducted to obtain additional evidence of the pathogenicity of these variants. The initial diagnosis of the probands was eoHM. We performed a further comprehensive examination of the available family members after mutations were detected inTRPM1orNYX.


RESULTS
Two novel compound heterozygous mutations inTRPM1were detected in the recruited families. The proband in family A with eoHM carried a c.2594C>T missense mutation in exon 19 and a c.669+3_669+6delAAGT splicing mutation, which was co-segregated with CSNB1 in this family. A patient in family B with a compound heterozygous missense mutation (c.3262G>A and c.3250T>C) was detected. No mutations were found inNYX. These two identified compound heterozygous mutations were not found in the 96 normal controls. After further examination of the family members, the patients in family A could be diagnosed as eoHM with CSNB1. However due to the limited clinic data, the patient in family B cloud not clearly diagnosed as CSNB1.


CONCLUSIONS
This study has expanded the mutation spectrum ofTRPM1for CSNB1 and additional studies are needed to elucidate the association between isolated high myopia andTRPM1andNYX.
Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China.
Lin
L
Zhou
Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China.
Tuo
T
Li
Department of Ophthalmology, Remin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China.
Yi-Qiao
YQ
Xing
Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China.
Yin
Y
Li
Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China.
Qing-Song
QS
Wu
Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China.
Mao-Ju
MJ
Zhang
NYX; TRPM1; complete congenital stationary night blindness; high myopia; mutations