Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with serum urate concentrations (18 new regions in or near TRIM46, INHBB, SFMBT1, TMEM171, VEGFA, BAZ1B, PRKAG2, STC1, HNF4G, A1CF, ATXN2, UBE2Q2, IGF1R, NFAT5, MAF, HLF, ACVR1B-ACVRL1 and B3GNT4). Associations for many of the loci were of similar magnitude in individuals of non-European ancestry. We further characterized these loci for associations with gout, transcript expression and the fractional excretion of urate. Network analyses implicate the inhibins-activins signaling pathways and glucose metabolism in systemic urate control. New candidate genes for serum urate concentration highlight the importance of metabolic control of urate production and excretion, which may have implications for the treatment and prevention of gout.

Chronic kidney disease (CKD), impairment of kidney function, is a serious public health problem, and the assessment of genetic factors influencing kidney function has substantial clinical relevance. Here, we report a meta-analysis of genome-wide association studies for kidney function–related traits, including 71,149 east Asian individuals from 18 studies in 11 population-, hospital- or family-based cohorts, conducted as part of the Asian Genetic Epidemiology Network (AGEN). Our meta-analysis identified 17 loci newly associated with kidney function–related traits, including the concentrations of blood urea nitrogen, uric acid and serum creatinine and estimated glomerular filtration rate based on serum creatinine levels (eGFRcrea) (P < 5.0 × 10−8). We further examined these loci with in silico replication in individuals of European ancestry from the KidneyGen, CKDGen and GUGC consortia, including a combined total of ~110,347 individuals. We identify pleiotropic associations among these loci with kidney function–related traits and risk of CKD. These findings provide new insights into the genetics of kidney function.

The beta zero-thalassemia codon 39 nonsense mutation predominant in Sardinia is severe, and homozygotes are transfusion dependent. Two-thirds of beta zero 39 alleles are linked to A gamma T (haplotype II). One-fourth are linked to A gamma I (haplotypes I and IX), as is the mild beta +-thalassemia -87 C-->G mutation (haplotype VIII). beta +/beta zero-Thalassemia VIII/II compound heterozygotes have significantly higher A gamma I:A gamma T (23:7) than beta zero-thalassemia I/II (24:20) or IX/II (16:17) cases. This suggests that the beta + -87 mutation is associated with elevated gamma expression in cis, which may contribute to the lack of transfusion-dependence in beta +/beta zero cases.

From 1980 to 1991, 6.3% of the adult population of the province of Sassari, Northern Sardinia, underwent voluntary β‐thalassemia screening. Of the 28 000 subjects examined, 15.7% proved to be heterozygotes for β‐thalassemia. In addition, the screening of 7500 students in 26 villages in Sassari province fixed the frequency of β‐thalassemia in this part of Sardinia at 10.4%. Of the 539 couples at risk to be expected from this figure, the screening detected 43% (234). The data suggest that inductive screening played a major role in the efficiency of this preventive β‐thalassemia program. Follow up of 221 pregnancies found to be at risk for homozygous β‐thalassemia and referred to the Antenatal Diagnosis Service, Cagliari, Southern Sardinia, showed that antenatal diagnosis was carried out in 80% of them. The overall percentage of couples refusing antenatal diagnosis was 10.8%, but over the years the acceptance rate for the procedure increased from 87% to 96%. Atypical hematological findings in 1.5% of 468 members of the couples at risk required globin chain synthesis and molecular analyses to define the precise β‐thalassemia genotype. Heterogeneous “mild”β‐thalassemia mutations as well as coexisting δ‐thalassemia were found in silent type I and type II β‐thalassemia carriers which, without chain synthesis and DNA investigations, would have escaped detection.

The -117(G-->A)A gamma hereditary persistence of fetal hemoglobin (Greek HPFH) and beta zero 39-thal mutations are rather frequent in Sardinia so that their interaction is to be expected. Characterization of eight compound heterozygotes for these defects indicated that HPFH was linked to haplotype VII and beta zero 39-thal to haplotype II. Haplotype II beta zero 39-thal chromosome carries the A gamma T gene which is a useful marker of gamma-gene expression. Since the Hb F level in these compound heterozygotes was significantly higher than in 46 -117 HPFH carriers, the A gamma I, A gamma T, and G gamma globin level was determined. A gamma T was underexpressed while G gamma was significantly increased, which suggest that in -117 A gamma HPFH/beta zero 39-thal healthy subjects the increase in Hb F production is determined only by the -117 mutated A gamma gene and the adjacent G gamma gene.