[Mutation screening of the TYR and P gene in three patients with oculocutaneous albinism].
OBJECTIVE
To identify the mutations of the tyrosinase gene (TYR) and P gene in patients with oculocutaneous albinism (OCA).


METHODS
Polymerase chain reaction (PCR) and denaturing high performance liquid chromatography (DHPLC) were applied to detect the mutations in all exons of TYR gene and P gene. Then DNA sequencing and restriction endonuclease analysis were used to confirm the mutations detected by DHPLC. Novel mutations were screened in 100 unrelated persons with normal phenotypes to exclude the possibility of polymorphism.


RESULTS
Two mutations were detected in the P gene of the three patients and none in TYR gene. Heterozygous mutation of T450M in exon 13 of the P gene was detected in patient 1. Patient 2 had a heterozygous mutation of T450M in exon 13 and a heterozygous mutation of G775R in exon 23 of the P gene. Patient 3 had a heterozygous mutation of G775R as well. Restriction endonuclease analysis of the P gene exon 13 showed that the Oli I site had partly disappeared resulting from the heterozygous mutation T450M in patient 1 and patient 2, but not in 100 unrelated individuals. The heterozygous mutation T450M is a novel mutation.


CONCLUSIONS
Gene diagnosis of OCA can be carried out effectively by combining PCR, DHPLC, DNA sequencing and restriction endonuclease analysis.
Dai
Can
C
The Institute of Reproduction and Stem Cell Engineering, Xiangya Medical College, Central South University, People's Republic of China.
Li
Wen
W
Gao
Bodi
B
Li
Lu-yun
LY
Lu
Guang-xiu
GX
D016115:Albinism, Oculocutaneous / Q000235:genetics*; D001483:Base Sequence; D004156:Catechol Oxidase / Q000235:genetics*; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D005260:Female; D022861:Hermanski-Pudlak Syndrome / Q000235:genetics; D006801:Humans; D014442:Monophenol Monooxygenase / Q000235:genetics*; D009154:Mutation; D055815:Young Adult
D004156:Catechol Oxidase; D014442:Monophenol Monooxygenase