Autosomal recessive congenital cataract in captive‐bred vervet monkeys (Chlorocebus aethiops)

Abstract

Although the three missense mutations in GCNT2 have a benign effect, a possibility exists that the candidate genes (GCNT2, HSF4 and CRYAA) might harbour mutations that are responsible for total congenital cataract.

Mutational analysis of BFSP1, CRYBB1, GALK1, and GJA8 in captive‐bred vervet monkeys (Chlorocebus aethiops)

“…As previously reported, only 8% of the vervet colony presented with total congenital cataract of which six families have been identified . Thus far, mutations in different congenital cataract genes have been reported from this colony . In the current study, seven of the eight novel sequence variants identified in the four screened genes were predicted to be disease‐causing.…”

“…To further support the notion that the variants identified in this study may be responsible for cataract development within the aforementioned colony, a comprehensive summary was conducted between the current and previously reported study of which the same cataract animals were used. Both studies identified 23 sequence variants in seven genes ( CRYAA , HSF4 , GCNT2 , BFSP1 , CRYBB1 , GALK1 , and GJA8 ) of which eight were missense and 15 silent.…”

“…The selected vervet monkeys were maintained at PUDAC/SAMRC according to the South African National Standard for the Care and Use of Animals for Scientific Purposes (South African Bureau of Standards, SANS 10386, 2008) . Similar housing, environmental, and diet conditions previously reported were employed . Twenty‐four vervet monkeys were selected based on their cataract phenotype and assigned into two groups.…”

“…Although rodents have been largely used for cataract genetic studies and reported to be the ideal model, in a colony of 180 captive‐bred vervet monkeys ( Chlorocebus aethiops ) maintained at Primate Unit and Delft Animal Centre (PUDAC/SAMRC), 12 individuals presented a spontaneous case of total congenital cataract (Figure ); however, the parents were asymptomatic . The clinical presentation of cataract in this colony was observed between the ages of three months to a year.…”

“…Based on the reported findings in this colony, it is clear that the cataract phenotype is of autosomal recessive genetic origin . Consequently, some of the autosomal recessive genes have been screened in this colony and mutations have been identified in crystalline alpha A ( CRYAA ), glucosaminyl (N‐acetyl) transferase 2 ( GCNT2 ), and heat‐shock transcription factor 4 ( HSF4 ) . Therefore, this study will further identify mutations in the remaining genes ( BFSP1, CRYBB1 , GALK1, and GJA8 ) using a combination of clinical, molecular biological, and bioinformatics strategies.…”