直接檢測雙鏈核酸中的堿基序列一直是一個無法解決的難題。在3月21日的國際知名網(wǎng)上開放雜志PloS ONE上，Ingeneus Research公司會發(fā)表一篇名為“雜聚三鏈基因組檢測方法分析人類基因組樣本中的病原或單核苷酸多態(tài)性”（Heteropolymeric Triplex-Based Genomic Assay to Detect Pathogens or Single-Nucleotide Polymorphisms in Human Genomic Samples）的文章,。
在文章中，研究人員給出了從樣本得到的病原分析數(shù)據(jù),，以及人類基因組雙鏈DNA和SNP分析結(jié)果,。這些分析能夠平行進行，并且可能在室溫下進行,。在5分鐘后,，研究人員能夠監(jiān)控反應(yīng)情況。這種高靈敏診斷分析能夠?qū)崿F(xiàn)對人類基因組雙鏈樣本中堿基序列的直接檢測，無需再使用PCR方法,，從而避免了這種方法的內(nèi)在問題并費用,。
Ingeneus Research的首席科學(xué)家Jasmine Daksis表示，他們已經(jīng)逐漸研制出了雜聚三鏈分析（heteropolymeric triplex）,。研究人員首先從合成的50-mer雙鏈靶標開始,，開發(fā)出了能夠分析人類基因組樣本的方法。這項分析利用YOYO-1(一種bisintercalator)來解壓縮雙鏈靶標,，這樣使雙鏈核酸能更容易與oligo ssDNA探針反應(yīng),。雙鏈中任何序列都能被特異性分析。研究人員推測特定的三鏈結(jié)合創(chuàng)造出另外的凹槽供另外的YOYO-1分子插入,。
該公司的研究團隊決定不將注意力集中在改善探針化學(xué)性質(zhì)方面,，轉(zhuǎn)而開發(fā)一種流體注射設(shè)備。這種叫做Genome Flow的設(shè)備使用了FIALab裝置的硬件,。研究人員希望能夠盡快發(fā)表利用Genome Flow設(shè)備進行基因組樣本病原或SNP的三鏈分析,。
部分英文原文：
PloS ONE，F(xiàn)ebruary 16, 2007; Accepted: February 25, 2007; Published: March 21, 2007
Heteropolymeric Triplex-Based Genomic Assay® to Detect Pathogens or Single-Nucleotide Polymorphisms in Human Genomic Samples
Jasmine I. Daksis*, Glen H. Erikson
Ingeneus Research, Mississauga, Ontario, Canada
Human genomic samples are complex and are considered difficult to assay directly without denaturation or PCR amplification. We report the use of a base-specific heteropolymeric triplex, formed by native duplex genomic target and an oligonucleotide third strand probe, to assay for low copy pathogen genomes present in a sample also containing human genomic duplex DNA, or to assay human genomic duplex DNA for Single Nucleotide Polymorphisms (SNP), without PCR amplification. Wild-type and mutant probes are used to identify triplexes containing FVL G1691A, MTHFR C677T and CFTR mutations. The specific triplex structure forms rapidly at room temperature in solution and may be detected without a separation step. YOYO-1, a fluorescent bis-intercalator, promotes and signals the formation of the specific triplex. Genomic duplexes may be assayed homogeneously with single base pair resolution. The specific triple-stranded structures of the assay may approximate homologous recombination intermediates, which various models suggest may form in either the major or minor groove of the duplex. The bases of the stable duplex target are rendered specifically reactive to the bases of the probe because of the activity of intercalated YOYO-1, which is known to decondense duplex locally 1.3 fold. This may approximate the local decondensation effected by recombination proteins such as RecA in vivo. Our assay, while involving triplex formation, is sui generis, as it is not homopurine sequence-dependent, as are “canonical triplexes”. Rather, the base pair-specific heteropolymeric triplex of the assay is conformation-dependent. The highly sensitive diagnostic assay we present allows for the direct detection of base sequence in genomic duplex samples, including those containing human genomic duplex DNA, thereby bypassing the inherent problems and cost associated with conventional PCR based diagnostic assays.
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