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Candidate gene analysis in Rett syndrome and the identification of 21 SNPs in Xq.

Rett syndrome (RTT) is an X-linked dominant neurodevelopmental disorder that affects females. Exclusion mapping studies using a new family with maternal inheritance of RTT defined Xq28 as the candidate region for the RTT gene. Six candidate genes were selected for mutation analysis based on their established expression patterns and known functions in the CNS. These are: Glutamate receptor subunit 3 (GLUR3), GABA receptor subunit alpha 3 (GABRA3), GABA receptor subunit e1 (GABRE1), Vacuolar ATPase subunit 1 (VATPS1, XAP3), the human homologue of plexin 3-SEX (XAP6) and the Synaptobrevin-like protein (SYBL1). Major rearrangements involving these genes were excluded by Southern analysis. No disease-causing mutations were found, but several single-nucleotide polymorphisms (SNPs) were detected. These SNPs will be useful in future linkage analysis and whole-genome association studies for other diseases. The genomic characterization of GLUR3 and GABRA3 will allow mutational analysis of these genes as candidates for other X-linked neurological disorders mapping to Xq25-Xq26 and Xq28.

Base Sequence↗

Haplotype diversity in 11 candidate genes across four populations.

Analysis of haplotypes based on multiple single-nucleotide polymorphisms (SNP) is becoming common for both candidate gene and fine-mapping studies. Before embarking on studies of haplotypes from genetically distinct populations, however, it is important to consider variation both in linkage disequilibrium (LD) and in haplotype frequencies within and across populations, as both vary. Such diversity will influence the choice of "tagging" SNPs for candidate gene or whole-genome association studies because some markers will not be polymorphic in all samples and some haplotypes will be poorly represented or completely absent. Here we analyze 11 genes, originally chosen as candidate genes for oral clefts, where multiple markers were genotyped on individuals from four populations. Estimated haplotype frequencies, measures of pairwise LD, and genetic diversity were computed for 135 European-Americans, 57 Chinese-Singaporeans, 45 Malay-Singaporeans, and 46 Indian-Singaporeans. Patterns of pairwise LD were compared across these four populations and haplotype frequencies were used to assess genetic variation. Although these populations are fairly similar in allele frequencies and overall patterns of LD, both haplotype frequencies and genetic diversity varied significantly across populations. Such haplotype diversity has implications for designing studies of association involving samples from genetically distinct populations.

Analysis of Variance↗

E2 sequence variations of HPV 16 among patients with cervical neoplasia seen in the Indian subcontinent.

OBJECTIVES: Specific nucleotide variations in the E2 DNA sequence were looked for in samples with an intact human papillomavirus (HPV) 16 episomal E2 DNA. METHODS: Ninety-two women, 76 with invasive cervical carcinoma and 16 with cervical intraepithelial neoplasia (CIN) were recruited. HPV DNA typing was performed by polymerase chain reaction (PCR) based restriction fragment length polymorphism (RFLP). Intact episomal E2 DNA of HPV 16 was detected by PCR. Important nucleotide variations in samples with amplifiable E2 DNA were detected by RFLP. Nucleotide sequencing was performed on representative samples to confirm RFLP findings. RESULTS: A total of 89 (96.7%) women were positive for HPV DNA. Of these, 56 (63%) were positive for HPV 16, and of these, 38 (68%) were positive for intact episomal HPV 16 E2 DNA while 18 (32%) were negative. Samples with intact episomal HPV 16 E2 DNA sequences were grouped into four different digestion profiles I to IV based on RFLP patterns. Digestion patterns revealed absence of any sequence variations in samples with digestion profile I and presence of a 2983 A-G variation in those with profile II. Samples with digestion profiles III and IV revealed three variations in the hinge region (3516 C-A, 3538 A-C, 3566 T-G) and two in the DNA binding domain (3684 C-A, 3694 T-A) of the E2 sequence. Sequencing performed on representative samples confirmed RFLP findings. CONCLUSIONS: PCR-RFLP helped in the identification of important HPV 16 E2 sequence variations, circumventing the need for sequencing. The presence of the nucleotide variations in positions that could alter the biological and immunological functions of the E2 protein combined with its increased occurrence in this study bring out the importance of these variations.

Base Sequence↗

Detection of genomic variation in Providencia stuartii clinical isolates by analysis of DNA restriction fragment length polymorphisms containing rRNA cistrons.

Chromosomal DNA from 26 strains of Providencia stuartii isolated mainly in hospitals in the United Kingdom and reference strains of P. stuartii, P. rustigianii, and Proteus vulgaris were digested with the restriction endonucleases EcoRI and HindIII. After electrophoresis in agarose gels, the fragments were subjected to Southern blot hybridization analysis with a biotin-labeled cDNA probe transcribed from a mixture of 16S and 23S rRNA from P. stuartii NCTC 11800T. The pattern of bands (the rDNA fingerprint), which depended on restriction fragment length polymorphisms containing rRNA genes, was used as a measure of minor genomic variation within and between species. The P. stuartii clinical isolates had similar total digest patterns, but the rDNA fingerprints revealed some heterogeneity between strains, with EcoRI digests providing better strain discrimination than HindIII. Such rDNA fingerprints comprised between five and seven bands with sizes in the range of 5 to 28 kilobases. The 11 different EcoRI patterns were compared by numerical analysis, and several groups or subgroups of strains were identified. Over half (15 of 26) of the urease-negative isolates (subgroups Aa and Ab) had patterns that differed only by the presence or absence of a 25-kilobase band. Urease-negative strains from other clinical material were more heterogeneous in their patterns. No correlation was apparent between strain pattern group and urease production or geographic location of isolate. The P. stuartii rDNA fingerprints were quite distinct from those of allied Providencia and Proteus species and provided a more sensitive measure of minor genomic differences than total DNA digests did.

DNA Probes↗

Quantifying the intragenic distribution of human disease mutations.

A wide variety of functional domains exist within human genes. Since different domains vary in their roles regarding overall gene function, the ability for a mutation in a gene region to produce disease varies among domains. We tested two hypotheses regarding distributions of mutations among functional domains by using (1) sets of single nucleotide disease mutations for six genes (CFTR, TSC2, G6PD, PAX6, RS1, and PAH) and (2) sets of polymorphic replacement and silent mutations found in two genes (CFTR and TSC2). First, we tested the null hypothesis that sets of mutations are uniformly distributed among functional domains within genes. Second, we tested the null hypothesis that disease mutations are distributed among gene regions according to expectations derived from the distribution of evolutionary conserved and variable amino acid sites throughout each gene. In contrast to the mainly uniform distribution of sets of silent and polymorphic mutations, sets of disease mutations generally rejected the null hypotheses of both uniform and evolutionary-influenced distributions. Although the disease mutation data showed a better agreement with the evolutionary-derived expectations, disease mutations were found to be statistically overabundant in conserved domains, and under-represented in variable regions, even after accounting for amino acid site variability of domains over long-term evolutionary history. This finding suggests that there is a non-additive influence of amino acid site conservation on the observed intragenic distribution of disease mutations, and underscores the importance of understanding the patterns of neutral amino acid substitutions permitted in a gene over long-term evolutionary history.

Conserved Sequence↗

Reliable high-throughput genotyping and loss-of-heterozygosity detection in formalin-fixed, paraffin-embedded tumors using single nucleotide polymorphism arrays.

Most human cancers show genetic instabilities leading to allelic imbalances, including loss of heterozygosity (LOH). Single nucleotide polymorphism (SNP) arrays can be used to detect LOH. Currently, these arrays require intact genomic DNA as obtained from frozen tissue; however, for most cancer cases, only low-quality DNA from formalin-fixed, paraffin-embedded (FFPE) tissue is available. In this study, we tested Illumina BeadArrays to genotype FFPE tissue and detect LOH/allelic imbalances in matched colorectal tumor and normal tissue. Genotypes were compared between leukocyte and FFPE normal tissue as well as between frozen and FFPE tumor tissue. Identical genotypes and LOH profiles were obtained from normal and tumor isolates. LOH was mainly observed on chromosomes 4, 5q, 12q, 14q, 15q, 17p, 18, and 20p, which are commonly detected regions in colorectal cancer. LOH profiles of the BeadArrays were compared with profiles obtained by Affymetrix GeneChip 10K arrays, showing identical LOH patterns. These data show that genome-wide genotyping of FFPE tissue with the BeadArray gives reliable results and is a powerful technique for LOH analysis.

Colorectal Neoplasms↗

Th2 cell-selective enhancement of human IL13 transcription by IL13-1112C>T, a polymorphism associated with allergic inflammation.

IL-13 is a central mediator of allergic inflammation. The single nucleotide polymorphism IL13-1112C>T (rs1800925) is associated with allergic phenotypes in ethnically distinct populations, but the underlying mechanism(s) remain unknown. Using in vivo, in vitro, and in silico analysis, we show that the IL13-1112T allele enhanced IL13 promoter activity in primary human and murine CD4(+) Th2 lymphocytes. Increased expression of IL13-1112T in Th2 cells was associated with the creation of a Yin-Yang 1 binding site that overlapped a STAT motif involved in negative regulation of IL13 expression and attenuated STAT6-mediated transcriptional repression. Because IL-13 secretion was increased in IL13-1112TT homozygotes, we propose that increased expression of IL13-1112T in vivo may underlie its association with susceptibility to allergic inflammation. Interestingly, IL13-1112T had opposite transcriptional effects in nonpolarized CD4(+) T cells, paralleled by distinct patterns of DNA-protein interactions at the IL13 promoter. Our findings suggest the nuclear milieu dictates the functional outcome of genetic variation.

Animals↗

Genotyping Cryptosporidium parvum with an hsp70 single-nucleotide polymorphism microarray.

We investigated the application of an oligonucleotide microarray to (i) specifically detect Cryptosporidium spp., (ii) differentiate between closely related C. parvum isolates and Cryptosporidium species, and (iii) differentiate between principle genotypes known to infect humans. A microarray of 68 capture probes targeting seven single-nucleotide polymorphisms (SNPs) within a 190-bp region of the hsp70 gene of Cryptosporidium parvum was constructed. Labeled hsp70 targets were generated by PCR with biotin- or Cy3-labeled primers. Hybridization conditions were optimized for hybridization time, temperature, and salt concentration. Two genotype I C. parvum isolates (TU502 and UG502), two C. parvum genotype II isolates (Iowa and GCH1), and DNAs from 22 non-Cryptosporidium sp. organisms were used to test method specificity. Only DNAs from C. parvum isolates produced labeled amplicons that could be hybridized to and detected on the array. Hybridization patterns between genotypes were visually distinct, but identification of SNPs required statistical analysis of the signal intensity data. The results indicated that correct mismatch discrimination could be achieved for all seven SNPs for the UG502 isolate, five of seven SNPs for the TU502 isolate, and six of seven SNPs for both the Iowa and GCH1 isolates. Even without perfect mismatch discrimination, the microarray method unambiguously distinguished between genotype I and genotype II isolates and demonstrated the potential to differentiate between other isolates and species on a single microarray. This method may provide a powerful new tool for water utilities and public health officials for assessing point and nonpoint source contamination of water supplies.

Animals↗

Indications of linkage and association of Gilles de la Tourette syndrome in two independent family samples: 17q25 is a putative susceptibility region.

Gilles de la Tourette syndrome (GTS) is characterized by multiple motor and phonic tics and high comorbidity rates with other neurobehavioral disorders. It is hypothesized that frontal-subcortical pathways and a complex genetic background are involved in the etiopathogenesis of the disorder. The genetic basis of GTS remains elusive. However, several genomic regions have been implicated. Among them, 17q25 appears to be of special interest, as suggested by various independent investigators. In the present study, we explored the possibility that 17q25 contributes to the genetic component of GTS. The initial scan of chromosome 17 performed on two large pedigrees provided a nonparametric LOD score of 2.41 near D17S928. Fine mapping with 17 additional microsatellite markers increased the peak to 2.61 (P=.002). The original families, as well as two additional pedigrees, were genotyped for 25 single-nucleotide polymorphisms (SNPs), with a focus on three genes in the indicated region that could play a role in the development of GTS, on the basis of their function and expression profile. Multiple three-marker haplotypes spanning all three genes studied provided highly significant association results (P<.001). An independent sample of 96 small families with one or two children affected with GTS was also studied. Of the 25 SNPs, 3 were associated with GTS at a statistically significant level. The transmission/disequilibrium test for a three-site haplotype moving window again provided multiple positive results. The background linkage disequilibrium (LD) of the region was studied in eight populations of European origin. A complicated pattern was revealed, with the pairwise tests producing unexpectedly high LD values at the telomeric TBCD gene. In conclusion, our findings warrant the further investigation of 17q25 as a candidate susceptibility region for GTS.

C-Reactive Protein↗

Nested PCR allows the characterization of TaqI and PstI RFLPs in the second exon of the caprine MHC class II DRB gene.

A nested polymerase chain reaction (PCR) method has been developed to obtain a specific amplification of the second exon of the caprine MHC class II DRB gene. The specificity of this method has been verified by cloning and sequencing the PCR product and comparing its sequence to 21 previously published caprine DRB second exon allelic variants. Nucleotide identity between this sequence (Caae-DRB23) and other caprine DRB alleles ranged between 85.6% (Caae-DRB22) and 96.5% (Caae-DRB5). Caae-DRB5 and Caae-DRB23 sequences diverged in five amino acid substitutions (70, 71, 73, 74, 78), all of them placed at the antigen binding site. Likewise, the restriction polymorphism of the caprine DRB second exon has been analyzed and two different restriction patterns have been found depending on the presence or absence of a TaqI site and a PstI site at positions 122 bp and 241 bp of the PCR product respectively. TaqI and PstI RFLPs were also analyzed in other artiodactyla species. While PstI RFLP was found not only in goats but also in cattle, sheep and pigs, TaqI RFLP was only detected in goats. In all of these species close associations were detected between the presence of TaqI and PstI restriction sites and amino acid substitutions at positions 40 and 78 respectively, suggesting that PCR restriction fragment length polymorphism (RFLP) could be a useful tool in relating amino acid substitutions at critical positions with disease resistance.

Amino Acid Sequence↗

Nonrandom patterns of simple and cryptic triplet repeats in coding and noncoding sequences.

Triplet repeats of the sequence purine, purine, and pyrimidine [RRY(i)] are frequent and often polymorphic in humans. Some RRY(i) are composed predominantly of a continuous repeat of one sequence [simple RRY(i)], but the majority are cryptic RRY(i) that are not obvious until the bases are classified into R or Y before the full extent of the repeat becomes apparent. RRY(i) can be divided into 18 classes based on predominant nucleotides. These classes are highly nonrandom in abundance and in location within genes. In humans, simple or cryptic RRY(i), in which AAT or AAC triplets predominate, are preferentially located 3' of Alu repeats. RRY(i) with a predominance of AGC or GGC show a dramatic enrichment in coding sequence, and GGC also shows a dramatic enrichment in 5' untranslated regions of genes. Characterization of RRY(i) present in coding regions identify 10 protein motifs (An, Dn, Hn, Pn, Qn, Tn, GnS0-3Gm, (G/S)n, (S/G/N)n, and (L/P)n). Six of the protein motifs appear predominantly in DNA-binding proteins/transcription factors. Alignment of homologous protein sequences from other mammals reveals that both simple and cryptic RRY(i) are a major source of deletions or insertions in the genes that contain them. Cryptic RRY(i) may be candidates for triplet repeat genetic diseases and, when mutated in somatic cells, may contribute to carcinogenesis.

Animals↗

Cerebellum development and schizophrenia: an association study of the human homeogene Engrailed 2.

Epidemiological data and family studies in schizophrenia show that genetic factors contribute to the vulnerability to this disorder. The homeogene Engrailed 2 (EN2) is specifically involved in patterning the region that gives rise to the cerebellum and controls the plasticity of midbrain dopaminergic neurons. We carried out an association study for a CA repeat polymorphism located in the 3' region of the homeogene EN2. The subjects consisted of 165 patients with schizophrenia and 97 controls matched for age and ethnicity from a French Caucasian population. We found no significant association of schizophrenia with this bi-nucleotide repeat polymorphism of the EN2 gene.

Adult↗

cDNA sequence and chromosomal localization of the mouse parvalbumin gene, Pva.

In the homozygous condition, the mutation adr (arrested development of righting response) of the mouse causes a myotonia and a drastic reduction of the Ca2+-binding protein parvalbumin (PV) in fast muscles. Using a rat PV probe, a mouse cDNA clone was isolated from a lambda gt11 wild-type fast-muscle library and its nucleotide sequence was determined. The protein coding and the 3' nontranslated regions of the mouse gene show extensive homology with the rat PV gene. The result of Southern blot hybridization is consistent with a single copy gene for parvalbumin. Restriction fragment length polymorphisms (RFLPs) between Mus musculus domesticus (e.g. C57BL/6) and Mus spretus (SPE) were detected with the enzymes Eco RI, Pst I, and Sst I. The restriction fragment patterns of DNA samples from 65 individual offspring of (C57BL/6 x SPE)F1 x C57BL/6 backcrosses were tested with the PV probe and matched, for linkage detection, to pre-existing patterns established with various RFLP probes on the same samples. A co-distribution of PV-RFLPs with Pvt-1 and Mlvi-2, which had been localized on chromosome 15, was detected. Thus, the structural gene for PV, designated Pva, maps to chromosome 15 of the mouse whereas the adr mutation shows no linkage with markers on this chromosome. Gene locus homology between chromosome 15 of the mouse and chromosome 22 of man (which carries the human PV gene) is discussed.

Amino Acid Sequence↗

Estimating the rate of gene conversion on human chromosome 21.

There is a growing recognition that gene conversion can be an important factor in shaping fine-scale patterns of linkage disequilibrium in the human genome. We devised simple multilocus summary statistics for estimating gene-conversion rates from genomewide polymorphism data sets. In addition to being computationally feasible for very large data sets, these summaries were designed to yield robust estimates of gene-conversion rates in the presence of variation in crossing-over rates. Using our summaries, we analyzed 21,840 biallelic single-nucleotide polymorphisms (SNPs) on human chromosome 21. Our results indicate that models including both crossing over and gene conversion fit the overall short-range data (0-5 kb) of chromosome 21 much better than do models including crossing over alone. The estimated ratio of gene-conversion rate to crossing-over rate has a range of 1.6-9.4, depending on the assumed conversion tract length (in the range of 500-50 bp). Removal of the 5,696 SNPs that occur in known mutational hotspots (CpG sites) did not significantly change our conclusions, suggesting that recurrent mutations alone cannot explain our data.

Chromosome Aberrations↗

Tumor necrosis factor-alpha gene -308G>A polymorphism is associated with ST-elevation myocardial infarction and with high plasma levels of biochemical ischemia markers.

OBJECTIVES: As is well known, acute myocardial infarction presents two electrocardiogram (EKG) patterns, ST-elevation (STEMI) and no ST-elevation (NSTEMI), characterized by different coronary artery thrombotic occlusion. Growing evidence shows that inflammation plays a central role in the pathogenesis of acute myocardial infarction. Among the factors that promote inflammation and arterial thrombosis, one of the most important is the proinflammatory cytokine tumor necrosis factor-alpha. The expression of this cytokine is modulated by a polymorphism located at nucleotide -308 of tumor necrosis factor-alpha promoter gene. The objective of our study is to verify whether tumor necrosis factor-alpha -308 polymorphism is associated with risk of acute myocardial infarction (STEMI and NSTEMI) or with biochemical myocardial ischemia markers, such as troponin I, creatine kinase-MB, lactate dehydrogenase and myoglobin. METHODS: We analyzed tumor necrosis factor-alpha -308 polymorphism in a total of 603 study participants: 293 elderly patients affected by acute myocardial infarction (STEMI and NSTEMI) and 310 healthy controls. RESULTS: We found that individuals carrying the tumor necrosis factor-alpha -308 AG+AA genotypes are significantly more represented among acute myocardial infarction patients affected by STEMI than among NSTEMI patients (OR = 1.86, 95% CI 1.08-3.21, p = 0.027) and healthy controls (OR = 1.64, 95% CI 1.03-2.64, p = 0.046). Furthermore, the patients carrying tumor necrosis factor-alpha -308 AG+AA genotypes displayed significant increased levels of biochemical myocardial ischemia markers. CONCLUSIONS: Our study shows a significant association between the tumor necrosis factor-alpha -308 polymorphism and the occurrence of STEMI, and suggests that the tumor necrosis factor-alpha -308 polymorphism could play a role in the pathogenesis of cardiac ischemic damage, AA+AG genotype carrier individuals being likely to be affected by more severe ischemic damage than the rest of the population.

Aged↗

[Distribution of hepatitis B virus genotype among population of Dong, Miao minority and Han in Guizhou].

OBJECTIVE: To study the distribution of hepatitis B virus (HBV) genotype in population of Dong, Miao minority and Han in Guizhou. METHODS: S region nucleotides were compared in 127 strains whole sequence of HBV and three restriction enzymes which can be used for genotyping were found by DNA software analysis system. The partial gene fragment of HBV S region was amplified by nested polymerase chain reaction (nPCR). The products were digested with Mbo I, BstN I or BsmA I and subjected to electrophoresis on agarose gel, respectively. The patterns of restriction fragment length polymorphism (RFLP) were analysed. The genotypes were determined by nPCR-RFLP in 166 asymptomatic HBV carriers (ASC), including 48 Dong minority, 52 Miao minority and 66 Han subjects. Some of the ASC were also analysed by direct sequencing of PCR products. RESULTS: The nPCR-RFLP method was simple and accurate. Of the 166 ASC, 138 (83.13%) were genotype B, and 28 (16.87%) were genotype C. Of the 48 Dong minority subjects, 47 (97.2%) were genotype B and 1 (2.08%) was type C. Of the 52 Miao minority subjects, 49 (94.23%) were genotype B and 3 (5.77%) were genotype C. Of the 66 Han subjects, 42 (63.64%) were genotype B and 24 (36.36%) were genotype C. There was a statistical significance in the distribution of genotype C between Dong, Miao minority and Han (7.85% vs 36.36% P less than 0.005). CONCLUSION: Genotype B and C exist in Guizhou and genotype B is the major genotype. Genotype C is found more frequently in Han than in Dong and Miao minority.

Adolescent↗

Probability of a segregating pattern in a sample of DNA sequences.

Mutations that result in segregating sites (polymorphic sites) in a sample of DNA sequences can be classified into different types. A pattern of segregating sites is an array of the numbers of various types of mutations. Using an urn model, the probability of a pattern of segregating sites can be expressed as a recurrence equation and its value can be computed sequentially. Among those that can be computed by this method are the probability of obtaining k external mutations (mutations that occur in external branches of the genealogy of a sample), the probability of obtaining k internal mutations (mutations that occur in internal branches), the probability of obtaining k singletons (segregating sites at which one of the two segregating nucleotides is present in only one sequence), and the probability of obtaining k non-singletons. Two applications of the method are discussed. One is a maximum likelihood estimation of straight theta and another is a Bayesian statistical test of the hypothesis of neutral mutations.

Bayes Theorem↗

Integration of HapMap-based SNP pattern analysis and gene expression profiling reveals common SNP profiles for cancer therapy outcome predictor genes.

Recent completion of the initial phase of a haplotype map of human genome (www.hapmap.org) provides opportunity for integrative analysis on a genome-wide scale of microarray-based gene expression profiling and SNP variation patterns for discovery of cancer-causing genes and genetic markers of therapy outcome. Here we applied this approach for analysis of SNPs of cancer-associated genes, expression profiles of which predicts the likelihood of treatment failure and death after therapy in patients diagnosed with multiple types of cancer. Unexpectedly, this analysis reveals a common SNP pattern for a majority (60 of 74; 81%) of analyzed cancer treatment outcome predictor (CTOP) genes. Our analysis suggests that heritable germ-line genetic variations driven by geographically localized form of natural selection determining population differentiations may have a significant impact on cancer treatment outcome by influencing the individual's gene expression profile. We demonstrate a translational utility of this approach by building a highly informative CTOP algorithm combining prognostic power of multiple gene expression-based CTOP models derived from signatures of oncogenic pathways associated with activation of BMI1; Myc; Her2/neu; Ras; beta-catenin; Suz12; E2F; and CCND1 oncogenes. Application of a CTOP algorithm to large databases of early-stage breast and prostate tumors identifies cancer patients with 100% probability of a cure with existing cancer therapies as well as patients with nearly 100% likelihood of treatment failure, thus providing a clinically feasible framework essential for introduction of rational evidence-based individualized therapy selection and prescription protocols. Our analysis indicates that genetic determinants of human disease susceptibility and severity are encoded by population differentiation SNP variants. Evolution of these SNPs is driven by geographically-localized form of natural selection causing population differentiation. Recent analysis identifies a class of SNPs regulating gene expression in normal individuals and likely determining unique genome-wide expression profiles of each individual. We propose that critical disease-causing combinations of SNP variants arise from SNPs regulating mRNA levels and determining genome-wide haplotype patterns of individual's disease susceptibility.

Biomarkers, Tumor↗