Utilizzo della tecnologia microchip per l'identificazione di geni candidati responsabili dell'aumento di HbF.

Expression of fetal globin is silenced normally in adult life; however, determinants linked and/or unlinked to the globin-gene clusters could modify Hb F expression so it persists into adults. Increased expression in adults offers hope as a cure for sickle cell disease (SCD) and b thalassemia, since formation of FS hybrids in SCD inhibits deoxy Hb S polymerization while increased fetal chain expression compensates partially for decreased adult b-globin chains in b thalassemia. Characterization and controlled manipulation of high Hb F determinants is critical to decreasing clinical severity of these life-threatening genetic diseases, which result in high morbidity and mortality worldwide. We report on analysis of a unique b-thalassemia cohort from Sardinia who present with either 1) a mild, non-transfusion-dependent (NTD) form expressing high Hb F, or with 2) a severe, transfusion-dependent (TD) form expressing low Hb F. Both groups are homozygous for the b39 chain-termination mutation and lack adult b globin. Genome-wide DNA arrays were run on 14 TD and 14 NTD patients using the Affymetrix 500K (500,568 SNPs) SNP chip platforms. The average sample cali rates were 94.3% for the 500K chip. Additional samples are being analyzed in an attempt to achieve sufficient power to reach genome-wide significance.