Long-term exposure to inorganic arsenic from well water was associated with an increased prevalence of cerebrovascular disease, especially cerebral infarction.

Autoimmune polyglandular syndrome type 1 (APS1), also known as autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), is an autosomal recessive disorder characterized by the failure of several endocrine glands as well as nonendocrine organs. The autoimmune regulator (AIRE) gene responsible for APS1 on chromosome 21q22.3 has recently been identified. Here, we have characterized mutations in the AIRE gene by direct DNA sequencing in 16 unrelated APS1 families ascertained mainly from the USA. Our analyses identified four different mutations (a 13-bp deletion, a 2-bp insertion, one nonsense mutation, and one potential splice/donor site mutation) that are likely to be pathogenic. Fifty-six percent (9/16) of the patients contained at least one copy of a 13-bp deletion (1094-1106del) in exon 8 (seven homozygotes and two compound heterozygotes). A nonsense mutation (R257X) in exon 6 was also found in 31.3% (5/16) of the USA patients. These data are important for genetic diagnosis and counseling for families with autoimmune endocrine syndromes.

Metabolic enzymes involved in benzene activation or detoxification, including NAD(P)H, quinone oxidoreductase 1 (NQO1), cytochrome P450 2E1 (CYP2E1), myeloperoxidase (MPO), glutathione-S-transferase mu-1 (GSTM1), and glutathione-S-transferase theta-1 (GSTT1), were studied for their roles in human susceptibility to benzene poisoning. The potential interactions of these metabolic enzymes with lifestyle factors such as cigarette smoking and alcohol consumption were also explored. We studied 156 benzene-poisoning patients and 152 workers occupationally exposed to benzene in South China. Sequencing, denaturing HPLC, restriction fragment-length polymorphism, and polymerase chain reaction were used to detect polymorphisms on the promoters and complete coding regions of NQO1, CYP2E1, MPO, and the null genotypes of GSTM1 and GSTT1. Seventeen single nucleotide polymorphisms (SNPs) were identified in NQO1, CYP2E1, and MPO genes, including 6 novel SNPs in CYP2E1 and MPO. Of the subjects who smoked and drank alcohol, an 8.15-fold [95% confidence interval (CI), 1.43-46.50] and a 21.50-fold (95% CI, 2.79-165.79) increased risk of benzene poisoning, respectively, were observed among the subjects with two copies of NQO1 with a C-to-T substitution in cDNA at nucleotide 609 (c.609 C>T variation; i.e., NQO1 c.609 T/T) compared to those with the heterozygous or wild (NQO1 c.609 C/T and c.609 C/C) genotypes. Our data also indicated that individuals with CYP2E1 c.-1293 C/C and c.-1293 G/C, and NQO1 c.609 T/T, and GSTT1 null genotypes tended to be more susceptible to benzene toxicity. Our results suggest that the combined effect of polymorphisms in NQO1, CYP2E1, and GSTT1 genes and lifestyle factors might contribute to benzene poisoning.

Graves' disease is known to be HLA-D associated; however, the primary loci involved remain unclear. We examined HLA genotypes of DRB1 and DQB1 plus DRB3 subtypes using PCR-based sequence-