Implementation of an optimized strategy for genetic testing of the Chinese patients with oculocutaneous albinism.

BACKGROUND

Oculocutaneous albinism (OCA) is a relatively common inherited disorder in all populations worldwide. The mutational spectra of OCA are population-specific.

OBJECTIVE

Based on our previous molecular epidemiological studies, we have implemented an optimized strategy for the genetic testing of Chinese OCA patients.

METHODS

Genomic DNA was extracted from the blood samples of 52 clinically diagnosed OCA patients and 100 unaffected subjects. The amplified DNA segments were screened for mutations of TYR, OCA2, TYRP1, SLC45A2 and HPS1 by direct sequencing. To exclude the previously unidentified alleles (PUAs) from polymorphisms, samples from 100 unaffected controls were sequenced for the same regions of variations.

RESULTS

Among the 52 OCA patients, 26 (50.0%) were found mutations on TYR gene, 8 (15.4%) on OCA2, 12 (23.1%) on SLC45A2, 2 (3.8%) on HPS1, and 4 (7.7%) patients uncharacterized. We identified 18 PUAs in these patients, 2 in TYR, 7 in OCA2, 8 in SLC45A2, and 1 in HPS1.

CONCLUSION

The optimized method to screen the OCA mutations is efficiently implemented in the routine genetic testing of Chinese OCA patients accompanied with genetic counseling.