Type I oculocutaneous albinism (OCA1) is an autosomal recessive disorder, which 
is caused by the reduction or the absence of tyrosinase activity in melanocytes 
of the skin, hair and eyes. Although tyrosinase mutations of OCA1 have been 
extensively analyzed in most populations worldwide, there is no systemic study 
of OCA1 mutation in Chinese patients. By use of single strand conformation 
polymorphism and direct sequencing, we had detected 21 mutant alleles out of 24 
OCA1 chromosomes screened (87.5%). Detected mutant alleles include one splicing 
site, three insertion/deletion and five missense mutations, of which the 
splicing site nucleotide alteration (IVS 1-3C>G) and two each of the 
insertion/deletion (232-233 ins GGG and 861-862 del TT) and missense mutations 
(Cys 289 Gly and Trp 400 Leu) are novel. The ins/del mutations accounts for 
about 37.5% in Chinese OCA1 alleles. The 232-233 ins GGG, one of the novel 
mutations, was found to be most frequent (25%) among the OCA1 alleles in 
Chinese. Through this study, we found that while some of the OCA mutant alleles 
were identified in other populations, ethnic difference still exists. Hum Mutat 
14:542, 1999.