Oculocutaneous albinism (OCA) is an autosomal recessive disorder characterized 
by hypopigmentation in eyes, hair and skin, accompanied with vision loss. 
Currently, six genes have been identified as causative genes for non-syndromic 
OCA (OCA-1∼4, 6, 7), and ten genes for syndromic OCA (HPS-1-9, CHS-1). Genetic 
counseling of 51 Chinese OCA families (39 OCA-1 with mutations in the TYR gene, 
6 OCA-2 with mutations in the OCA2 gene, 4 OCA-4 with mutations in the SLC45A2 
gene, 1 HPS-1 (Hermansky-Pudlak syndrome-1) with mutation in the HPS1 gene, and 
1 mixed OCA-1 and OCA-4) led us to perform the prenatal genetic testing of OCA 
using amniotic fluid cells through the implementation of our optimized strategy. 
In our cohort, eleven previously unidentified alleles (PUAs) (5 in TYR, 2 in 
OCA2, and 4 in SLC45A2) were found. Three missense PUAs (p.C112R, p.H363R and 
p.G379V of TYR) and one in-frame deletional PUA (p.S222del of SLC24A5) led to 
fetuses with OCA when co-inherited with other disease causative alleles. Three 
PUAs (p.P152H and p.W272X of TYR, p.A486T of SLC24A5) identified in the OCA 
probands did not co-transmit with known pathological alleles and thus gave rise 
to unaffected fetuses. Four PUAs (p.Q83X and p.A658T of TYR, p.G161R and p.G366R 
of SLC24A5) did not transmit to the unaffected fetuses. In addition, the 
in vitro transfection assays showed that the p.S192Y variant of TYR produced 
less pigment compared to the wild-type allele. A fetus with a digenic carrier of 
OCA-1 and OCA-4 was unaffected. In combination with functional assays, the 
family inheritance pattern is useful for the evaluation of pathogenicity of PUAs 
and genetic counseling of OCA.