Rapid genetic analysis of oculocutaneous albinism (OCA1) using denaturing high performance liquid chromatography (DHPLC) system.
OBJECTIVE
To present the prenatal genetic diagnoses and counseling for two cases of oculocutaneous albinism (OCA) type I family by detection of mutations in the OCA1 gene by denaturing high performance liquid chromatography (DHPLC) system and a review of the literature.


METHODS
All DNA samples were extracted from peripheral whole blood and amniocentesis-derived cells. Mutation analysis was performed for all five coding exons of the TYR gene, which were amplified by PCR. DHPLC was used for heteroduplex detection and sequence analysis was performed to demonstrate the mutation loci.


RESULTS
Case 1: After sampling of blood from the family members and performing amniocentesis of the fetus, it was demonstrated that the affected boy and the female fetus were shown to be compound heterozygotes for mutations in the TYR gene. In addition, it was shown that the parents were carriers of the two mutations. However, the couple chose to keep the baby. Case 2: Mutation analysis of the DNA of the siblings revealed two heterozygous mutations in the TYR gene. Her husband is free of the disease. According to the principles of autosomal recessive inheritance, the incidence of affected offspring is very low.


CONCLUSIONS
Herein we introduce a novel application for molecular diagnostic of DHPLC coupled with direct sequencing, which can provide an effective and exact diagnosis in patients with albinism. Clinicians should be cognizant of the risk of OCA inheritance by the offspring through careful identification of genetic mutations and the inheritance mode, both important to ensure comprehensive genetic counseling.
Department of Obstetrics and Gynecology, National Taiwan University Hospital, No. 7 Chung-Shan South Road, Taipei, Taiwan.
Shin-Yu
SY
Lin
Shu-Chin
SC
Chien
Yi-Ning
YN
Su
Chien-Nan
CN
Lee
Chih-Ping
CP
Chen
D000328:Adult; D016115:Albinism, Oculocutaneous / Q000175:diagnosis* / Q000235:genetics*; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D004252:DNA Mutational Analysis / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D008297:Male; D014442:Monophenol Monooxygenase / Q000235:genetics*; D009691:Nucleic Acid Denaturation; D010375:Pedigree; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000295:instrumentation / Q000379:methods
D014442:Monophenol Monooxygenase