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Results for “Single nucleotide polymorphisms (SNPs)”

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PubMed2003

An exponential dispersion model for the distribution of human single nucleotide polymorphisms.

An analysis of 1.42 million human single nucleotide polymorphisms (SNPs), mapped by the International SNP Map Working Group, revealed an apparent power function relationship between the estimated variance and mean number of SNPs per sample bin. This relationship could be explained by the assumption that a scale invariant Poisson gamma (PG) exponential dispersion model could describe the distribution of SNPs within the bins. In this model the sample bins would contain random (Poisson distributed) numbers of identical by descent genomic segments, each with independently distributed and gamma distributed numbers of SNPs. This model was both qualitatively and quantitatively consistent with the conventional coalescent model. It agreed with the empirical cumulative distribution functions derived from the SNP maps as well as with simulated data. The model was used to estimate the heterozygosity pi, and the mean number and size of haplotype blocks for each chromosome. These estimates were consistent with measurements from conventional studies. This PG model thus provides an alternative to Monte Carlo simulation for description of the distribution of SNPs.

Computer Simulation↗
PubMed2006

Clinical impact of MMP and TIMP gene polymorphisms in gastric cancer.

Gastric cancers express enhanced levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Single-nucleotide polymorphisms (SNPs) in MMP and TIMP genes may be associated with disease susceptibility and might also affect their antigen expression. We studied the genotype distribution and allele frequencies of SNPs of MMP-2, -7, -8 and -9 and TIMP-1 and -2 in gastric cancer patients in relation to tumour progression, patient survival and tissue antigen expression. The genotype distribution and allele frequencies were similar in gastric cancer patients and controls, except for MMP-7(-181A>G). In addition, the genotype distribution of MMP-7(-181A>G) was associated with Helicobacter pylori status (chi(2) 7.8, P=0.005) and tumour-related survival of the patients. Single-nucleotide polymorphism TIMP-2(303C>T) correlated significantly with the WHO classification (chi(2) 5.9, P=0.03) and also strongly with tumour-related survival (log rank 11.74, P=0.0006). Single-nucleotide polymorphisms of MMP-2, -8, -9 and TIMP-1 were not associated with tumour-related survival. Only the gene promoter MMP-2(-1306C>T) polymorphism correlated significantly with the protein level within the tumours. First-order dendrogram cluster analysis combined with Cox analysis identified the MMP-7(-181A>G) and TIMP-2(303C>T) polymorphism combination to have a major impact on patients survival outcome. We conclude that MMP-related SNPs, especially MMP-7(-181A>G) and TIMP-2(303C>T), may be helpful in identifying gastric cancer patients with a poor clinical outcome.

Adult↗
PubMed2007

Genetic association between the PRKCH gene encoding protein kinase Ceta isozyme and rheumatoid arthritis in the Japanese population.

OBJECTIVE: Analyses of families with rheumatoid arthritis (RA) have suggested the presence of a putative susceptibility locus on chromosome 14q21-23. This large population-based genetic association study was undertaken to examine this region. METHODS: A 2-stage case-control association study of 950 unrelated Japanese patients with RA and 950 healthy controls was performed using >400 gene-based common single-nucleotide polymorphisms (SNPs). RESULTS: Multiple SNPs in the PRKCH gene encoding the eta isozyme of protein kinase C (PKCeta) showed significant single-locus disease associations, the most significant being SNP c.427+8134C>T (odds ratio 0.72, 95% confidence interval 0.62-0.83, P = 5.9 x 10(-5)). Each RA-associated SNP was consistently mapped to 3 distinct regions of strong linkage disequilibrium (i.e., linkage disequilibrium or haplotype blocks) in the PRKCH gene locus, suggesting that multiple causal variants influence disease susceptibility. Significant SNPs included a novel common missense polymorphism of the PRKCH gene, V374I (rs2230500), which lies within the ATP-binding site that is highly conserved among PKC superfamily members. In circulating lymphocytes, PRKCH messenger RNA was expressed at higher levels in resting T cells (CD4(+) or CD8(+)) than in B cells (CD19(+)) or monocytes (CD14(+)) and was significantly down-regulated through immune responses. CONCLUSION: Our results provide evidence of the involvement of PRKCH as a susceptibility gene for RA in the Japanese population. Dysregulation of PKCeta signal transduction pathway(s) may confer increased risk of RA through aberrant T cell-mediated autoimmune responses.

Adult↗
PubMed2002

Detection of single nucleotide polymorphisms within the Listeria genus using an 'asymmetric' fluorogenic probe set and fluorescence resonance energy transfer based-PCR.

AIMS: We describe a novel and inexpensive fluorescence energy transfer (FRET)-based PCR protocol to distinguish single nucleotide polymorphisms (SNPs) within the genus Listeria. METHODS AND RESULTS: Sequence information for the 16S rRNA gene of representative Listeria species was used to design genus-specific primers and two species-specific probes that differed in sequence by one single nucleotide. The probes were 5' labelled with either fluorescein or Texas Red, quenched with a shorter yet complementary 3' dimethyl-amino-phenyloazo benzoic acid (DABCYL) labelled oligonucleotide, and then incorporated into a previously reported 'asymmetric' FRET-based PCR detection protocol. CONCLUSIONS: Listeria monocytogenes could be readily distinguished from other members of the Listeria genus after PCR amplification and measurement of endpoint fluorescence at two different wavelengths. SIGNIFICANCE AND IMPACT OF THE STUDY: The relatively low cost and high flexibility of this system will benefit laboratories in their efforts to develop rapid and specific methods to detect minor sequence differences between related microorganisms.

Fluorescence Resonance Energy Transfer↗
PubMed2001

Single nucleotide polymorphisms of the human M1 muscarinic acetylcholine receptor gene.

The gene encoding the human muscarinic receptor, type 1 (CHRM1), was genotyped from 245 samples of the Coriell Collection (Coriell Institute for Medical Research, Camden, NJ). Fifteen single nucleotide polymorphisms (SNPs) were discovered, 9 of which are located in the coding region of the receptor. Of these, 8 represent synonymous SNPs, indicating that CHRM1 is highly conserved in humans. Only a single allele was found to contain a nonsynonymous SNP, which encodes an amino acid change of Cys to Arg at position 417. This may have functional consequences because a C417S point mutation in rat M1 was previously shown to affect receptor binding and coupling. Furthermore, 0 of 4 SNPs within CHRM1 previously deduced from sequencing of the human genome were found in this study despite a prediction that a majority of such inferred SNPs are accurate. The consensus sequence of CHRM1 obtained in our study differs from the deposited reference sequence (AC NM_000738) in 2 adjacent nucleotides, leading to a V173M change, suggesting a sequencing error in the reference sequence. The extraordinary sequence conservation of the CHRM1 gene-coding region was unexpected as M1-knockout mice show only minimal functional impairments.

Amino Acid Substitution↗
PubMed2005

Characterization of linkage disequilibrium structure, mutation history, and tagging SNPs, and their use in association analyses: ELAC2 and familial early-onset prostate cancer.

In association analyses, it is critical that informative single-nucleotide polymorphisms (SNPs) be selected for study and utilized appropriately. We sequenced 38 kb, including exons of ELAC2, promoter region and conserved upstream intergenic sequences. A comprehensive characterization of linkage disequilibrium (LD) structure and mutation history was performed using our principal components analysis (PCA) method and a phylogenetic analysis. We identified a complex pattern of LD structure consistent with the occurrence of both recombination and mutation events within ELAC2. Four overlapping and noncontiguous LD groups were defined. Eight tagging SNPs (tSNPs) were identified, accounting for over 90% of the genetic variation of the 19 total variants. We tested associations between familial early-onset prostate cancer (PRCA) and each variant independently and in haplotypes. We performed these tests using all 19 variants and the 8 tSNPs; the results using tSNP haplotypes accurately represent the association evidence for the full haplotypes. We observed increased evidence for association when SNPs were analyzed in haplotypes. The phylogenetic analysis indicated three haplotypes, clustered farthest from the root-node, all of which were found more often in cases than controls. These three haplotypes together showed the best evidence of association with familial, early-onset PRCA (P=0.0024; odds ratio=2.23; 95% CI, 1.33-3.74), indicating possible allelic heterogeneity. Our results suggest that 8 tSNPs are required to comprehensively assess associations in ELAC2, and that haplotypes should be considered for analysis, and that a knowledge of mutation history may be helpful in parsing allelic heterogeneity and suggesting combinations of haplotypes to be tested.

Aged↗
PubMed2004

The genomic distribution of population substructure in four populations using 8,525 autosomal SNPs.

Understanding the nature of evolutionary relationships among persons and populations is important for the efficient application of genome science to biomedical research. We have analysed 8,525 autosomal single nucleotide polymorphisms (SNPs) in 84 individuals from four populations: African-American, European-American, Chinese and Japanese. Individual relationships were reconstructed using the allele sharing distance and the neighbour-joining tree making method. Trees show clear clustering according to population, with the root branching from the African-American clade. The African-American cluster is much less star-like than European-American and East Asian clusters, primarily because of admixture. Furthermore, on the East Asian branch, all ten Chinese individuals cluster together and all ten Japanese individuals cluster together. Using positional information, we demonstrate strong correlations between inter-marker distance and both locus-specific FST (the proportion of total variation due to differentiation) levels and branch lengths. Chromosomal maps of the distribution of locus-specific branch lengths were constructed by combining these data with other published SNP markers (total of 33,704 SNPs). These maps clearly illustrate a non-uniform distribution of human genetic substructure, an instructional and useful paradigm for education and research.

Genetics, Population↗
PubMed2003

Phylogenetic relationships among Ehrlichia ruminantium isolates.

Ehrlichia ruminantium, the causative agent of heartwater, is a tick-borne pathogen infecting ruminants throughout sub-Saharan Africa and on some Caribbean islands. The most reliable test for E. ruminantium is PCR-based, but this gives positive results in some areas free of clinical heartwater and of the known Amblyomma spp. tick vectors. To investigate the molecular basis for this finding we have sequenced and carried out phylogenetic analysis of a range of genes from a number of E. ruminantium isolates. The genes include ribonuclease III and cytochrome c oxidase assembly protein genes (the pCS20 region), groESL, citrate synthase (gltA), and 16S ribosomal RNA. Relationships among major antigenic protein (map1) genes have been exhaustively investigated in a previous study that showed that the genes are variable in length, have non-synonymous mutations, and show no geographical specificity among isolates. The 16S sequences are highly conserved, except in the V1 loop region. The pCS20, groESL, and gltA genes show only single nucleotide polymorphisms (SNPs) dispersed throughout the sequenced regions. Phylogenetic analysis using pCS20 data differentiates the western African isolates into a single clade, which also includes a southern African isolate. All other southern African isolates and a Caribbean isolate fall into a further clade, which is subdivided into two groups. Sequence variation within this clade is greater than that within the western African clade, suggesting that E. ruminantium originated in southern Africa.

Africa South of the Sahara↗
PubMed2004

The TDI-FP assay in human Y chromosome SNP haplotyping.

One of the many commercial technologies for genotyping single nucleotide polymorphisms (SNPs) is template direct dye-terminator incorporation with fluorescence-polarization (TDI-FP assay). It is a single-base extension assay followed by reading the fluorescence polarization values in an appropriate instrument. We have evaluated the suitability of the TDI-FP technique to detect haploid uniparentally inherited DNA polymorphisms on the nonrecombining portion of the Y chromosome. A sample of 47 individuals has been genotyped for 8 Y chromosome biallelic markers. The SNP typing was blindly duplicated by the denaturing high-performance liquid chromatography (DHPLC) technique for comparison. In the cases under examination the TDI-FP assay was able to resolve an allelic state fully. Such a result showed 100% concordance indicating how efficiently the TDI assay can be used to genotype Y chromosome DNA SNPs. However, a percentage of indeterminate genotypes remained unresolved by simple visual inspection: it varied from 0% to 11% depending on the SNP locus and on the success of amplification. This is consistent with previous findings. A maximum likelihood classificatory analysis allowed some of the indeterminate genotypes to be assigned and some potentially misclassified samples to be identified. Their percentage remains relatively high despite retyping and therefore alternative techniques for these noncompliant situations are required.

Automation↗
PubMed2006

TAMAL: an integrated approach to choosing SNPs for genetic studies of human complex traits.

UNLABELLED: Investigators conducting studies of the molecular genetics of complex traits in humans often need rationally to select a set of single nucleotide polymorphisms (SNPs) from the hundreds or thousands available for a candidate gene. Accomplishing this requires integration of genomic data from distributed databases and is both time-consuming and error-prone. We developed the TAMAL (Technology And Money Are Limiting) web site to help identify promising SNPs for further investigation. For a given list of genes, TAMAL identifies SNPs that meet user-specified criteria (e.g. haplotype tagging SNPs or SNP predicted to lead to amino acid changes) from current versions of online resources (i.e. HapMap, Perlegen, Affymetrix, dbSNP and the UCSC genome browser). AVAILABILITY: TAMAL is a platform independent web-based application available free of charge at http://neoref.ils.unc.edu/tamal. SUPPLEMENTARY INFORMATION: http://neoref.ils.unc.edu/tamal/.

Chromosome Mapping↗
PubMed2004

Haplotypes and SNPs in 13 lipid-relevant genes explain most of the genetic variance in high-density lipoprotein and low-density lipoprotein cholesterol.

Single nucleotide polymorphisms (SNPs) and derived haplotypes within multiple genes may explain genetic variance in complex traits; however, this hypothesis has not been rigorously tested. In an earlier study we analyzed six genes and have now expanded this investigation to include 13. We studied 250 families including 1054 individuals and measured lipid phenotypes. We focused on low-density cholesterol (LDL), high-density cholesterol (HDL) and their ratio (LDL/HDL). A component analysis of the phenotypic variance relying on a standard genetic model' showed that the genetic variance on LDL explained 26%, on HDL explained 38% and on LDL/HDL explained 28% of the total variance, respectively. Genotyping of 93 SNPs in 13 lipid-relevant genes generated 230 haplotypes. The association of haplotypes in all the genes tested explained a major fraction of the genetic phenotypic variance component. For LDL, the association with haplotypes explained 67% and for HDL 58% of the genetic variance relative to the polygenic background. We conclude that these haplotypes explain most of the genetic variance in LDL, HDL and LDL/HDL in these representative German families. An analysis of the contribution to the genetic variance at each locus showed that APOE (50%), CETP (28%), LIPC (9%), APOB (8%) and LDLR (5%) influenced variation in LDL. LIPC (53%), CETP (25%), ABCA1 (10%), LPL (6%) and LDLR (6%) influenced the HDL variance. The LDL/HDL ratio was primarily influenced by APOE (36%), CETP (27%) and LIPC (31%). This expanded analysis substantially increases the explanation of genetic variance on these complex traits.

Cholesterol, HDL↗
PubMed2005

Association study of detoxification genes in age related macular degeneration.

BACKGROUND/AIMS: Age related macular degeneration (AMD) is a complex disorder leading to loss of central vision, and identification of risk factors associated with susceptibility to AMD has been a key objective for ophthalmic genetics research for almost a decade. This association study has examined genetic polymorphisms in 12 candidate genes as possible risk factors for predisposition to the development of the exudative variant of AMD in a Northern Irish population. The choice of genes was based on their function in the breakdown of industrial pollutants, cigarette smoke, defence against oxidative stress, or involvement in the general ageing process. METHODS: Up to five single nucleotide polymorphisms (SNPs) were typed for CYP1A1, CYP1A2, CYP2E1, CYP2D6, EPHX1, MnSOD, AhR, NAT2, CAT, GPX1, PON1, and ADPRT1 by multiplex snapshot single base primer extension method. Genes showing high linkage disequilibrium (LD) between SNPs were analysed by haplotype analysis. Genes showing low LD were assessed using individual SNPs based on genotypes. RESULTS: After correction for number of genes/SNPs tested, no significant association with AMD was found although several genes merit further investigation. This study suggests that a coding SNP in EPHX1 (Y113H) may be important in AMD and supports a previous observation of an association with exudative AMD. In addition, haplotype analysis highlighted ADPRT1, CYP2D6, and AhR as worthy of further study. CONCLUSION: This study has identified a number of genes requiring further investigation including EPHX1, ADPRT1, CYP2D6, and AhR.

Aged↗
PubMed2006

Transferability of tag SNPs to capture common genetic variation in DNA repair genes across multiple populations.

Genetic association studies can be made more cost-effective by exploiting linkage disequilibrium patterns between nearby single-nucleotide polymorphisms (SNPs). The International HapMap Project now offers a dense SNP map across the human genome in four population samples. One question is how well tag SNPs chosen from a resource like HapMap can capture common variation in independent disease samples. To address the issue of tag SNP transferability, we genotyped 2,783 SNPs across 61 genes (with a total span of 6 Mb) involved in DNA repair in 466 individuals from multiple populations. We picked tag SNPs in samples with European ancestry from the Centre d'Etude du Polymorphisme Humain, and evaluated coverage of common variation in the other samples. Our comparative analysis shows that common variation in non-African samples can be captured robustly with only marginal loss in terms of the maximum r2. We also evaluated the transferability of specified multi-marker haplotypes as predictors for untyped SNPs, and demonstrate that they provide equivalent coverage compared to single-marker tests (pairwise tags) while requiring fewer SNPs for genotyping. The efficacy of a tagging-based approach in studying genotype-phenotype correlations in complex traits is strongly supported by our empirical results.

Computational Biology↗
PubMed2006

Rapid identification of three functionally relevant polymorphisms in the OATP1B1 transporter gene using Pyrosequencing.

INTRODUCTION: Clinical evidence suggests there are three single nucleotide polymorphisms (SNPs) of the solute carrier organic anion transporter family member B1 (SLCO1B1) gene for which in vivo evidence for a functional relevance for organic anion transporter polypeptides subgroup C (OATP1B1, formerly OATP-C) has been provided. These genetic variants have been shown to lead to altered pharmacokinetics of OATP1B1 substrates, mainly pravastatin, but also the irinotecan metabolite SN-38, estrone-3-sulfate, and estradiol-17beta-glucuronide. The authors therefore developed reliable and quick screening assays to identify the SLCO1B1 SNPs -11187G>A, 388A>G and 521T>C, in order to facilitate the judgment of their clinical role and to identify allelic frequencies of SNPs and haplotypes in a Caucasian random sample. METHODS: Three simplex Pyrosequencing assays were developed and the three selected SLCO1B1 SNPs were screened for in 250 DNA samples from healthy young female and male unrelated volunteers of Caucasian ethnicity. SLCO1B1 haplotypes involving DNA positions -11187, 388 and 521 were identified by in silico haplotyping. RESULTS: A clear identification of the three single nucleotide polymorphisms in the 250 DNA samples was possible and was verified by routine implementation of 40 control samples obtained by conventional sequencing. The frequencies of the variant alleles -11187A, 388G and 521C were 0.09, 0.47 and 0.12, respectively. All observed frequencies of heterozygous of homozygous carriers of SLCO1B1 alleles were in agreement with the Hardy-Weinberg equilibrium. SLCO1B1 haplotypes reportedly associated with altered substrate pharmacokinetics, i.e., SLCO1B1*15B (-11187G/388G/521C) and *17 (-11187A/388G/521C), were found at allelic frequencies of 0.09 and 0.02, respectively. CONCLUSION: The presently developed Pyrosequencing assays allowed for quick and reliable identification of those SLCO1B1 SNPs that had been proposed to cause functional alternations in OATP1B1 with shown consequences for the pharmacokinetics of drugs that are OATP1B1 substrates.

Adult↗
PubMed2005

MilkProtChip--a microarray of SNPs in candidate genes associated with milk protein biosynthesis--development and validation.

MilkProtChip is an oligonucleotide microarray based on the arrayed primer extension (APEX) technique, allowing genotyping of single nucleotide polymorphisms (SNPs) in genes of interest for bovine milk protein biosynthesis. APEX consists of a sequencing reaction primed by an oligonucleotide anchored with its 5'end to a glass slide and terminating one nucleotide before the polymorphic site. The extension with one fluorescently labeled dideoxy nucleotide complementary to the template reveals the polymorphism. A total of 75 SNPs were selected among those associated directly or potentially with milk protein content. Among the 75 SNPs, 4 did not produce a positive signal. Most of the remaining SNPs produced a signal for both strands, except for 4 (one strand). In the validation step, 12 Polish Holstein bulls, 1 Polish Red bull, 1 bison (Bison bonasus), 11 Jersey cows and 25 Polish Holstein cows were screened to validate SNPs. Among the 71 selected SNPs--26 were found monoallelic, the rest showing at least two genotypes for the entire population under study. All the animals were earlier genotyped for 2-5 SNPs by PCR-RFLP and PCR sequencing and all showed complete concordance with APEX genotyping. APEX reactions showed relatively high signal frequencies: more than 0.9, 0.9-0.8 and below 0.8, for 65, 4 and 2 DNA samples, respectively. The primary application of the MilkProtChip is the simultaneous genotyping of dozens of SNPs to reveal and clarify the genetic background of milk protein biosynthesis. The chip may possibly be used for dairy cattle identification and paternity analysis, evolutionary studies, the evaluation of genetic distances between wild and domestic cattle breeds and the domestication history of bovine species.

Animals↗
PubMed2002

High-throughput genotyping of single nucleotide polymorphisms using new biplex invader technology.

The feasibility of large-scale genome-wide association studies of complex human disorders depends on the availability of accurate and efficient genotyping methods for single nucleotide polymorphisms (SNPs). We describe a new platform of the invader assay, a biplex assay, where both alleles are interrogated in a single reaction tube. The assay was evaluated on over 50 different SNPs, with over 20 SNPs genotyped in study cohorts of over 1500 individuals. We assessed the usefulness of the new platform in high-throughput genotyping and compared its accuracy to genotyping results obtained by the traditional monoplex invader assay, TaqMan genotyping and sequencing data. We present representative data for two SNPs in different genes (CD36 and protein tyrosine phosphatase 1beta) from a study cohort comprising over 1500 individuals with high or low-normal blood pressure. In this high-throughput application, the biplex invader assay is very accurate, with an error rate of <0.3% and a failure rate of 1.64%. The set-up of the assay is highly automated, facilitating the processing of large numbers of samples simultaneously. We present new analysis tools for the assignment of genotypes that further improve genotyping success. The biplex invader assay with its automated set-up and analysis offers a new efficient high-throughput genotyping platform that is suitable for association studies in large study cohorts.

Biotechnology↗
PubMed2005

Specific detection of bacillus anthracis using a TaqMan mismatch amplification mutation assay.

Single nucleotide polymorphisms (SNPs) are increasingly recognized as important diagnostic markers for the detection and differentiation of Bacillus anthracis. The use of SNP markers for identifying B. anthracis DNA in environmental samples containing genetically similar bacteria requires the ability to amplify and detect DNA with single nucleotide specificity. We designed a TaqMan mismatch amplification mutation assay (TaqMAMA) around a SNP in the plcR gene of B. anthracis. The assay permits specific, low-level detection (25 fg DNA) of this B. anthracis-specific SNP, even in the presence of environmental DNA extracts containing a 20,000-fold excess of the alternate allele. We anticipate that the ability to selectively amplify and detect low copy number DNAs with single nucleotide specificity will represent a valuable tool in the arena of biodefense and microbial forensics.

Bacillus anthracis↗
PubMed2003

An arabinogalactan protein associated with secondary cell wall formation in differentiating xylem of loblolly pine.

Arabinogalactan proteins (AGPs) are abundant plant proteoglycans implicated in plant growth and development. Here, we report the genetic characterization, partial purification and immunolocalization of a classical AGP (PtaAGP6, accession number AF101785) in loblolly pine (Pinus taeda L.). A PtaAGP6 full-length cDNA clone was expressed in bacteria. PtaAGP6 resembles tomato LeAGP-1 and Arabidopsis AtAGP17-19 in that they all possess a subdomain composed of basic amino acids. The accessibility of this domain in the glycoprotein makes it possible to label the PtaAGP6 epitopes on the cell surface or in the cell wall with polyclonal antibodies raised against this subdomain. The antibodies recognize the peptide of the basic subdomain and bind to the intact protein molecule. A soluble protein-containing fraction was purified from the differentiating xylem of pine trees by using beta-glucosyl Yariv reagent (beta-glcY) and was recognized by antibodies against the basic subdomain. Immunolocalization studies showed that the PtaAGP6 epitopes are restricted to a file of cells that just precede secondary cell wall thickening, suggesting roles in xylem differentiation and wood formation. The location of apparent labeling of the PtaAGP6 epitopes is separated from the location of lignin deposition. Multiple single nucleotide polymorphisms (SNPs) were detected in EST variants. Denaturing HPLC analysis of PCR products suggests that PtaAGP6 is encoded by a single gene. Mobility variation in denaturing gel electrophoresis was used to map PtaAGP6 SNPs to a site on linkage group 5.

Amino Acid Sequence↗