Genetic tools discriminate strains of Leishmania infantum isolated from humans and dogs in Sicily, Italy.

BACKGROUND: Leishmaniasis is one of the most important vector-borne diseases and it represents a serious world health problem affecting millions of people. High levels of Leishmania infections, affecting both humans and animals, are recognized among Italian regions. Among these, Sicily has one of the highest prevalence of Leishmania infection. METHODOLOGY/PRINCIPAL FINDINGS: Seventy-eight Leishmania strains isolated from human and animal samples across Sicily, were analyzed for the polymorphic k26-gene and genotypes were assigned according to the size of the PCR products. A multilocus microsatellite typing (MLMT) approach based on the analysis of 11 independent loci was used to investigate populations structure and genetic diversity of the isolated strains. Six L. infantum reference strains were included in the analysis for comparison. Bayesian clustering analysis of microsatellite data showed that all the isolated strains clustered in two genetically distinct populations, corresponding to human and canine isolates respectively. A further subdivision was observed between the two main groups, giving a good correlation between human strains and their geographic origin, conversely canine population showed a great genetic variability diffused in the territory. CONCLUSIONS/SIGNIFICANCE: Among the 78 Leishmania isolates, K26 analysis detected 71 samples (91%) as MON-1 zymodeme, confirming it as the predominant strain in Mediterranean area and 7 human samples (9%) as non-MON-1. MLMT gives important insights into the epidemiology of leishmaniases and allows characterization of different strains to a higher resolution than possible with zymodeme typing. Two main populations presented a strong correlation respect to the different hosts, exhibiting a co-circulation of two distinct populations of L. infantum. The population found in infected humans exhibited a correlation with geographic origin. These clusters could represent a geographically restricted population of strains with the same or related genotypes. This study can contribute to an understanding of Leishmania epidemiology, including the spread of reservoirs and sand fly vectors in the different foci of infection, characterizing parasites within the different hosts.

Vitiligo susceptibility and catalase gene polymorphisms in Sicilian population.

BACKGROUND: Catalase gene (CAT) polymorphisms were analyzed as responsible for the deficiency of catalase enzyme activity and concomitant accumulation of excessive hydrogen peroxide in vitiligo patients. Catalase is a well-known oxidative stress regulator that could play an important role in the pathogenesis of vitiligo. This study was conducted to evaluate three CAT gene polymorphisms (-89A/T, 389C/T, 419C/T) and their association with vitiligo susceptibility in Sicilian population. METHODS: Sixty out of 73 Sicilian patients with vitiligo were enrolled and submitted to CAT gene analysis. RESULTS: Contrary to the Northern part of Europe but likewise to the Mediterranean area, the frequency of the CAT genotypes in Sicily is equally distributed. Out of all CAT genotypes, only CAT-89 T/T frequency was found to be significantly higher amongst vitiligo patients than controls. CONCLUSIONS: Despite the involvement of the CAT enzyme in the pathogenesis of vitiligo, the biological significance of CAT gene polymorphisms is still controversial. With the only exception for CAT variant -89A/T, the other studied CAT gene polymorphisms (389C/T and 419C/T) might not to be associated with vitiligo in Sicilian population.

Refractory acne and 21-hydroxylase deficiency in a selected group of female patients.

BACKGROUND: Excessive androgen production, suspected in women when acne is accompanied by hirsutism and menstrual irregularities, may be due to congenital adrenal hyperplasia. This inherited disorder of cortisol biosynthesis is caused in more than 90-95% of all cases by 21-hydroxylase deficiency (21-OHD). The steroid 21-hydroxylase gene (CYP21) has a high degree of variability. OBJECTIVE: This study was conducted to evaluate CYP21 gene mutations in a selected group of women with papulopustular and comedonal acne refractory to treatment, irregular menses and hirsutism. METHODS: 30 out of 61 women enrolled underwent pelvic ultrasound examination and hormonal screening. In 9 patients with a polycystic ovary and hormonal pattern of adrenal hyperandrogenism a significant elevation of adrenocorticotropic hormone (ACTH) stimulated 17-hydroxyprogesterone was detected. These women positive in the ACTH stimulation test were submitted to CYP21 gene analysis. RESULTS: Genetic testing revealed several different point mutations and demonstrated that a cohort of patients resistant to acne therapy can be carriers or affected by non-classical 21-OHD (late onset). CONCLUSION: Persistent acne can be the unique presenting sign of non-classical 21-OHD. Evaluation of CYP21 gene mutations may identify female carriers or patients for genetic counselling.