AIM: To screen congenital cataract in the early stage using dual-specific probe technique composed of DNA hybridization and chromogenic probe.

METHODS: The mRNA was isolated from venous blood of 14 congenital cataract patients with autosomal dominant inheritance in 3 chromosomes. Based on genetic mutats of CRYAB gene, DNA probe, capture probe and signal probe were designed. The sandwich structures containing capture probe, DNA probe and signal probe was used to detect genetic mutants in 8 samples from one family; and ELISA was used to detect the contents fluctuation of Crystallin alpha B.

RESULTS: The dual-specific probe technique detected the minimum genetic mutation of Crystallin alpha B in congenital cataract samples, various mutations detection rate was between 99.5% and 99.7%. In ELISA detection, serum Crystallin alpha B level increased, and detection rate was 85.9%. Compared with ELISA assay, this novel assay was more sensitive.

CONCLUSION: The novel dual-specific probe method is quite convenient for detection of genetic mutants of congenital cataract; and for its high sensitivity and repeatability, it is of great potential in clinically prenatal diagnosis, and it might play significant roles in eugenic and superior nurture.