Porphyria Cutanea Tarda and HIV infection. Influence of multidrug resistance (MDR1) polymorphisms in exon 12 and 21

MELITO, VIVIANA; ZUCCOLI, JOHANNA; ROSSETTI, MARIA VICTORIA; PARERA, VICTORIA; LAVANDERA JIMENA; BATLLE, ALCIRA; BUZALEH ANA MARIA

Dusseldorf

Congreso; INTERNATIONAL CONGRESS ON PORPHYRINS AND PORPHYRIAS 2015; 2015

Porphyria Cutanea Tarda (PCT)is the most common Porphyria in Argentina, with a prevalence of 1:25,000. In this country,a high incidence (17%) of HIV infection in PCT patients is found. However, sincealmost all the HIV infected patients with PCT had additional risk factors forPorphyria manifestation, it is not yet clear if HIV infection is actually a precipitatedfactor for PCT. However, there have been many reports about PCT triggeringafter or during the therapy with antiretroviral drugs, even in the absence of aprecipitating agent. A number of polymorphisms in the multidrug resistancetransporter gene (MDR1) were found to be of clinical importance, among them: exon12 (c.1236 C>T), 21 (c.2677G>T/A) and 26 (c.3435 C>T) with highincidence in Caucasians. The frequency of the exon 26 was previously studiedproposing the influence of this polymorphism on PCT manifestation independentlyon HIV infection.Our aim was to further investigate if exons 12 and 21 MDR1 polymorphisms could influence theonset of PCT studying healthy individuals and patients with PCT and PCT-HIV. PCR-FRLP assay was used.The frequency of exon 12 was 0.33(control, n=39); 0.59 (PCT, n=29) and 0.35 (PCT-VIH, n=39), When exon 21 wasanalyzed, allelic frequency was 0.45 (control, n= 40); 0.48 (PCT, n= 41) and 0.62(PCT-VIH, n=34). The differences between control vs PCT and PCT vs PCT-VIH forexon 12 and control vs PCT-VIH for exon 21 were significant (p<0.05). Theanalysis of 1236T-2677T/A-3435T haplotypes wasperformed using SNPStats program. CCG wild type haplotype was predominant in control group followed by thepolymorphic TTT haplotype; while in PCT and PCT-HIV, TTT was more frequent. In conclusion, resultshere presented are in concordance with our earlier studies on exon 26, supportingthat PCT trigger could be related with a minor expression of MDR1 in both PCTgroups.