Haplotypes and diplotypes in thetryptase gene (TPSAB1 gene), a highlypolymorphic gene

  1. Hernández-Hernández, L 1
  2. Sanz, C 1
  3. García-Sánchez, M 1
  4. Pascual, M 1
  5. Lorente, F 1
  6. Dávila, I 1
  1. 1 Hospital Universitario de Salamanca

    Hospital Universitario de Salamanca

    Salamanca, España

    ROR https://ror.org/0131vfw26

EAACI Congress of the European Academy of Allergy and Clinical Immunology

ISSN: 0105-4538

Year of publication: 2012

Volume: 67

Issue: s96

Pages: 114-115

Congress: Congress of the European Academy of Allergy and Clinical Immunology

Type: Conference paper


JCR (Journal Impact Factor)

  • Year 2012
  • Journal Impact Factor: 5.883
  • Journal Impact Factor without self cites: 5.06
  • Article influence score: 1.627
  • Best Quartile: Q1
  • Area: IMMUNOLOGY Quartile: Q1 Rank in area: 19/137 (Ranking edition: SCIE)
  • Area: ALLERGY Quartile: Q1 Rank in area: 2/23 (Ranking edition: SCIE)

SCImago Journal Rank

  • Year 2012
  • SJR Journal Impact: 2.126
  • Best Quartile: Q1
  • Area: Immunology Quartile: Q1 Rank in area: 35/215
  • Area: Immunology and Allergy Quartile: Q1 Rank in area: 29/195

Scopus CiteScore

  • Year 2012
  • CiteScore of the Journal : 10.1
  • Area: Medicine (all) Percentile: 94
  • Area: Immunology and Allergy Percentile: 89
  • Area: Immunology Percentile: 87


Background:TPSAB1 gene codes for tryp-tase, a serine protease stored in the secre-tion granules of mast cells. It has beendescribed that this is a polymorphic genewith several described SNPs along this.TPSAB1 gene, which encodes the alpha-tryptase and beta-tryptase, is the moststudied from the functional point of view.It has a homology of 90% with TPSB2.This high degree of homology makes difficult the real characterization of theSNPs. The aim of this study is to analyzethe TPSAB1 gene SNPs in a population ofcontrol individuals.Method:A total of 110 healthy adult indi-viduals were included in this study withnormal serum tryptase levels. DNA frag-ments were amplified by PCR and subse-quently sequenced. The haplotype analysiswas carried out by the SNPAnalyzer on-line software. EM, Clark and PseudoGibbs Sampler (PGS) algorithms wereused, EM estimates haplotype frequencieswithin the given population, Clark isappropriate for homozygous genotypesand PGS uses conditional probabilities. Inorder to confirm the haplotypic character-ization and the resulting PCR fragmentswere cloned in three representative cases.Finally, the cloned DNA fragments weresequenced.Result:Combinations of the 17 mutationsprovided four haplotype combinationsobtained by EM algorithm with a fre-quency >0.05, four with Clark algorithmand three with PGS. The most frequenthaplotype is the haplotype 2 (ACGACGATGCTCCGGGT) and being the mostcommon in the population (8.5%). In ouranalysis the diplotype combinationobtained with higher frequency is GCGACGACGCTCCGGTG/GCGACGCCACTCCGGGT with a frequency of 0.025. Cloningallow us to confirm six haplotypes and toobtain two new ones All cloned samplesprovided more than two alleles.Conclusion:Given the large number ofcombinations obtained with the employedprograms and considering that more thanone gene could be simultaneously analyzed;cloning of PCR product is needed to avoidbiased results