Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice
<p>Abstract</p> <p>Background</p> <p>The detection of bitter-tasting compounds by the gustatory system is thought to alert animals to the presence of potentially toxic food. Some, if not all, bitter stimuli activate specific taste receptors, the T2Rs, which are expresse...
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| Format: | Article |
| Language: | English |
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BMC
2005-06-01
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| Series: | BMC Genetics |
| Online Access: | http://www.biomedcentral.com/1471-2156/6/32 |
| _version_ | 1818041058606448640 |
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| author | Munger Steven D Nelson Theodore M Boughter John D |
| author_facet | Munger Steven D Nelson Theodore M Boughter John D |
| author_sort | Munger Steven D |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>The detection of bitter-tasting compounds by the gustatory system is thought to alert animals to the presence of potentially toxic food. Some, if not all, bitter stimuli activate specific taste receptors, the T2Rs, which are expressed in subsets of taste receptor cells on the tongue and palate. However, there is evidence for both receptor-dependent and -independent transduction mechanisms for a number of bitter stimuli, including quinine hydrochloride (QHCl) and denatonium benzoate (DB).</p> <p>Results</p> <p>We used brief-access behavioral taste testing of BXD/Ty recombinant inbred (RI) mouse strains to map the major quantitative trait locus (QTL) for taste sensitivity to QHCl. This QTL is restricted to a ~5 Mb interval on chromosome 6 that includes 24 genes encoding T2Rs (<it>Tas2rs</it>). <it>Tas2rs </it>at this locus display in total 307 coding region single nucleotide polymorphisms (SNPs) between the two BXD/Ty RI parental strains, C57BL/6J (quinine-sensitive) and DBA/2J (quinine insensitive); approximately 50% of these mutations are silent. Individual RI lines contain exclusively either C57BL/6J or DBA/2J <it>Tas2r </it>alleles at this locus, and RI lines containing C57BL/6J <it>Tas2r </it>alleles are more sensitive to QHCl than are lines containing DBA/2J alleles. Thus, the entire <it>Tas2r </it>cluster comprises a large haplotype that correlates with quinine taster status.</p> <p>Conclusion</p> <p>These studies, the first using a taste-salient assay to map the major QTL for quinine taste, indicate that a T2R-dependent transduction cascade is responsible for the majority of strain variance in quinine taste sensitivity. Furthermore, the large number of polymorphisms within coding exons of the <it>Tas2r </it>cluster, coupled with evidence that inbred strains exhibit largely similar bitter taste phenotypes, suggest that T2R receptors are quite tolerant to variation.</p> |
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| format | Article |
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| institution | Directory Open Access Journal |
| issn | 1471-2156 |
| language | English |
| last_indexed | 2024-12-10T08:24:23Z |
| publishDate | 2005-06-01 |
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| record_format | Article |
| series | BMC Genetics |
| spelling | doaj.art-1fe5384ed2514aea9b207e856c2ffc702022-12-22T01:56:16ZengBMCBMC Genetics1471-21562005-06-01613210.1186/1471-2156-6-32Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred miceMunger Steven DNelson Theodore MBoughter John D<p>Abstract</p> <p>Background</p> <p>The detection of bitter-tasting compounds by the gustatory system is thought to alert animals to the presence of potentially toxic food. Some, if not all, bitter stimuli activate specific taste receptors, the T2Rs, which are expressed in subsets of taste receptor cells on the tongue and palate. However, there is evidence for both receptor-dependent and -independent transduction mechanisms for a number of bitter stimuli, including quinine hydrochloride (QHCl) and denatonium benzoate (DB).</p> <p>Results</p> <p>We used brief-access behavioral taste testing of BXD/Ty recombinant inbred (RI) mouse strains to map the major quantitative trait locus (QTL) for taste sensitivity to QHCl. This QTL is restricted to a ~5 Mb interval on chromosome 6 that includes 24 genes encoding T2Rs (<it>Tas2rs</it>). <it>Tas2rs </it>at this locus display in total 307 coding region single nucleotide polymorphisms (SNPs) between the two BXD/Ty RI parental strains, C57BL/6J (quinine-sensitive) and DBA/2J (quinine insensitive); approximately 50% of these mutations are silent. Individual RI lines contain exclusively either C57BL/6J or DBA/2J <it>Tas2r </it>alleles at this locus, and RI lines containing C57BL/6J <it>Tas2r </it>alleles are more sensitive to QHCl than are lines containing DBA/2J alleles. Thus, the entire <it>Tas2r </it>cluster comprises a large haplotype that correlates with quinine taster status.</p> <p>Conclusion</p> <p>These studies, the first using a taste-salient assay to map the major QTL for quinine taste, indicate that a T2R-dependent transduction cascade is responsible for the majority of strain variance in quinine taste sensitivity. Furthermore, the large number of polymorphisms within coding exons of the <it>Tas2r </it>cluster, coupled with evidence that inbred strains exhibit largely similar bitter taste phenotypes, suggest that T2R receptors are quite tolerant to variation.</p>http://www.biomedcentral.com/1471-2156/6/32 |
| spellingShingle | Munger Steven D Nelson Theodore M Boughter John D Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice BMC Genetics |
| title | Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| title_full | Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| title_fullStr | Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| title_full_unstemmed | Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| title_short | Haplotypes at the <it>Tas2r </it>locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| title_sort | haplotypes at the it tas2r it locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice |
| url | http://www.biomedcentral.com/1471-2156/6/32 |
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