Genes biallelic

Allele One form of a genetic locus, distinguished from other forms (= alleles) by its particular nucleotide or its coded amino acid sequence. Single nucleotide polymorphisms are biallelic, i.e., one base pair is exchanged with just one other base pair. In such a case, only two different alleles exist in the population for such a gene locus. However, several different alleles may exist in the population if the locus is defined by more than one nucleotide (i.e., microsatelhtes, haplotypes). Thus,... 

Dnmtl Maintenance (functions after replication on hemimethylated DNA to restore existing methylation patterns in vitro can methylate non-methylated DNA) associates with histone deacetylase Adult/Embryo DNMTD die in utero DNA in these embryos is hypomethylated, imprinted genes are biallelically expressed ES cells from DNMTl mice are viable and capable of de novo methylation... 

There is evidence implicating alpha-adrenoceptors in hypersalivation caused by clozapine, and it has been hypothesized that a biallelic polymorphism in the promoter region of the alpha2-adrenoceptor gene confers susceptibility to schizophrenia, which is associated with a clozapine-induced favorable therapeutic response and/or clozapine-induced hypersalivation (172). However, the results in 97 patients showed that the alpha2-adrenoceptor gene polymorphism did not play a major role in susceptibility to hypersalivation or the therapeutic response of patients with schizophrenia. 

Biallelic damage damage to both maternal and paternal copies of a gene. 

MSI is identified in 90% of HNPCC-related CRC as opposed to only 15% to 20% of sporadic CRC. MSI in sporadic CRC is attributed to inactivation of gene expression of hMLHl through biallelic methylation rather than as somatic mutations or loss of hetero2ygosity (LOH) as seen in HNPCC-related CRC. Further, patients whose tumors demonstrate MSI have better survival and better response to chemotherapy than those whose tumors do not express MSI. No association between tumor MSI and survival was seen, however, in young patients under the age of 30. ... 

Storlazzi CT, Von Steyern FV, Domanski HA, et al. Biallelic somatic inactivation of the NFl gene through chromosomal translocations in a sporadic neurofibroma. Int J Cancer. 2005 117 1055-1057. 

Pendreds syndrome is caused by biallelic mutations in the anion transporter SLC26A4 gene, originally referred to as PDS gene, which encodes pendrin. 

Patients with mutations in the monocarbox-ylate carrier exhibit intermittent hyperketotic metabolic acidosis. Patients with biallelic mutations have more profound acidosis than patients with a mutation on a single allele. The primary diagnostic method is sequencing of the MCTl gene. 

Nicod J, Bruhin D, Auer L, Vogt B, Frey FJ, Fer- 2092. rari P (2003) A biallelic gene polymorphism of CYP11B2 predicts increased aldosteroneto renin... 

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