ATP binding cassette transporter retina genotypes and age related macular degeneration: an analysis on exudative non-familial Japanese patients

Aim-To determine whether mutations in the Stargardt's disease gene, ATP bin ding cassette transporter retina (ABCR) affect the occurrence of age relate d macular degeneration (AMD) in Japanese nonfamilial patients. Methods-80 unrelated Japanese patients with AMD (67 males and 13 females; m ean age, 67.2 years) diagnosed by indocyanine green angiography and 100 age matched control subjects were studied. Among the AMD patients, 70 (87.5%) had choroidal neovascularisation of exudative type. Genomic DNA was purifie d from the total blood and 10 exons (exons 11, 23, 29, 32, 34, 37, 41, 43, 44, and 49) that have been reported to contain AMD associated mutations wer e amplified by polymerase chain reaction (PCR). The amplicons were analysed by the single strand conformation polymorphism (SSCP) method. The nucleoti de sequencing of the amplicons was determined when necessary. Results-Of the 10 exons, aberrant patterns of SSCP were detected in three e xons-exons 29, 41, and 43. In exon 29, an aberrant pattern was found in sev en of 80 patients (8.8%) and eight of 100 controls (8%). Sequencing of the PCR products revealed a heterozygous T1428M mutation which has been previou sly reported as one of the AMD associated mutations. Statistical analysis s howed that there was no significant difference in the occurrence of this mu tation between these AMD patients and the control groups (p = 0.86). In exo ns 23, 41, and 43, polymorphisms and sequence variations were found. Conclusion-No data to support the association between the ABCR gene mutatio ns and AMD of Japanese patients, especially that of the exudative type, wer e obtained in this molecular genetic analysis.