Blog
About

10
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Haplotype Frequency of G691S/S904S in the RET Proto-Onco-gene in Patients with Medullary Thyroid Carcinoma

      Read this article at

      ScienceOpenPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Medullary thyroid carcinoma (MTC) occurs in both sporadic (75%) and hereditary (25%) forms. The missense mutations of the REarranged during Transfection (RET) proto-oncogene in MTC development have been well demonstrated. The aim of this study was to investigate frequency of G691S/S904S haplotype in MTC patients and their relatives.

          Methods

          In this research 293 participants were studied, including 181 patients (102 female, 79 male) and 112 their relatives (58 female, 54 male). Genomic DNA was extracted from peripheral blood leucocytes using the standard Salting Out/Proteinase K method. Nucleotide change detection was performed using PCR and direct DNA sequencing methods.

          Results

          According to DNA sequencing results, 159 individuals (104 patients, 55 relatives) had both G691S (rs1799939) missense mutation in exon11 and S904S (rs1800863) synonymous mutation in exon 15 of RET proto-oncogene. The allele frequency of G691S/S904S haplotype was 21.15% in patients and 10.75% in their relatives.

          Conclusion

          The obtained data showed the frequency of G691S/S904S RET gene haplotype among Iranian MTC patients and their relatives. The G691S and S904S nucleotide changes were in complete linkage disequilibrium, so the results were grouped together and referred to as G691S/S904S haplotype. Further analysis is need to demonstrate the association between this haplotype and MTC development.

          Related collections

          Most cited references 18

          • Record: found
          • Abstract: found
          • Article: not found

          RET exon 11 (G691S) polymorphism is significantly more frequent in sporadic medullary thyroid carcinoma than in the general population.

          The RET protooncogene is constitutively activated by point mutations in hereditary medullary thyroid carcinomas (MTCs). RET somatic point mutations have also been reported in 40-50% of sporadic MTCs. Several single nucleotide polymorphisms of the RET gene have been described in the general population as well as in patients with MTC. These allelic variants do not seem to confer any transforming activity to the tyrosine kinase domain of the RET gene. Because the exon 11 RET polymorphism determines an important aminoacidic variation (G691S), we studied its frequency in 212 subjects, 106 sporadic MTC patients and 106 normal age-, sex-, race-, and geographic origin-matched controls. In 46 cases of sporadic MTCs, we also studied the cosegregation of somatic RET gene mutation and G691S polymorphism as well as the linkage of the polymorphism with RET germline mutation in 60 members of eight multiple endocrine neoplasia type 2 families. The influence of this polymorphism on the RET gene transcription has also been studied. In parallel we analyzed the frequencies of another three neutral polymorphisms (L769L, S836S, S904S). We found a statistically significant (P = 0.029) higher allelic frequency of G691S polymorphism in MTCs (27.83%) than that found in normal controls (18.86%), at variance with the three neutral polymorphisms whose frequencies were not different in patients and controls. With this study we excluded the influence of the G691S polymorphism on RET mRNA expression, the development of the somatic RET mutation, the linkage with the germline RET mutation, the younger onset of the MTCs, and the clinical outcome of the disease. A putative role of the G691S polymorphism as genetic modifier in the normal subjects remains to be established.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Current concepts in RET-related genetics, signaling and therapeutics.

            The receptor tyrosine kinase RET is expressed in cell lineages derived from the neural crest and has a key role in regulating cell proliferation, migration, differentiation and survival during embryogenesis. Germline and somatic mutations in RET that produce constitutively activated receptors cause the cancer syndrome multiple endocrine neoplasia type 2 and several endocrine and neural-crest-derived tumors, whereas mutations resulting in nonfunctional RET or lower expression of RET are found in individuals affected with Hirschsprung disease. This review focuses on the genetics and molecular mechanisms underlying the different inherited human neural-crest-related disorders in which RET dysfunction has a crucial role and discusses RET as a potential therapeutic target.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Polymorphisms in the initiators of RET (rearranged during transfection) signaling pathway and susceptibility to sporadic medullary thyroid carcinoma.

              Medullary thyroid carcinoma (MTC) is a characteristic tumor occurring in individuals with multiple endocrine neoplasia type 2 who carry germ-line mutations in RET (rearranged during transfection). However, most MTC occur in individuals without a family history. The objective of this study was to explore the possibility that susceptibility in these cases results from low penetrance alleles of RET, its coreceptors, and ligands. We carried out an association study in 135 sporadic MTC (sMTC) patients and 533 controls from the United Kingdom population. We analyzed 33 polymorphisms in all nine genes involved in the glial cell line-derived neurotropic factor receptor-alpha (GFRalpha)-RET complex. This is the first association study in which all genes involved in this complex have been investigated for susceptibility to sMTC. We did not find any association between single nucleotide polymorphisms in the exonic regions of the GFRalpha2, GFRalpha3, GFRalpha4, glial cell line-derived neurotropic factor, neurturin, or persephin genes and risk of developing sMTC. We found a strong association between the disease and specific haplotypes of RET. We not only confirmed the previously described association with G691S and S904S (for heterozygotes: odds ratio, 1.85; range, 1.22-2.82; P = 0.004), but we found a novel protective effect associated with a specific haplotype (odds ratio, 0.39; range, 0.21-0.72; P = 0.005) revealing the existence of different genetic variants in the RET oncogene that either increase or decrease risk of sMTC.
                Bookmark

                Author and article information

                Journal
                Iran J Public Health
                Iran. J. Public Health
                IJPH
                Iranian Journal of Public Health
                Tehran University of Medical Sciences
                2251-6085
                2251-6093
                February 2014
                : 43
                : 2
                : 235-240
                Affiliations
                Cellular and Molecular Research Center, Research Institute for Endocrine Sciences, Obesity Research Center, Shahid Beheshti University of Medical sciences , Tehran, Iran
                Author notes
                * Corresponding Author: Email: hedayati@ 123456endocrine.ac.ir
                Article
                IJPH-43-235
                4450692
                Copyright © Iranian Public Health Association & Tehran University of Medical Sciences

                This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License which allows users to read, copy, distribute and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited properly.

                Categories
                Original Article

                Public health

                thyroid cancer, medullary, ret proto-oncogene, g691s/s904s haplotype

                Comments

                Comment on this article