Establishment of personal protection method for life-style diseases : type IV hyperlipoproteinemia as a model case

本研究的目的是建立预防生活方式相关疾病的个体方法，特别是高脂血症作为一个模型病例，因为我们认为，关注个体遗传弱点预防生活方式相关疾病是切实可行的。我们已经阐明了原发性IV型高脂血症的病因是杂合子脂蛋白脂酶（LPL）缺乏的遗传背景和叠加的甘油三酯合成刺激因子在其遗传背景。这意味着没有甘油三酯合成刺激因子的LPL杂合子缺陷者不表现高甘油三酯血症。杂合型LPL缺乏的个体必须比具有正常LPL基因的两个等位基因的人更小心甘油三酯合成刺激因子的叠加，例如饮酒。杂合子LPL畸变的可靠和准确的遗传诊断是发展个体预防方法所必需的。 ...更多信息 高甘油三酯血症。我们发展和改进了LPL和肝甘油三酯脂肪酶质量测定方法、LPL基因直接测序方法、不忽略突变的PCR方法和高脂血症致动脉粥样硬化小致密LDL检测方法。在此基础上，我们积累了日本人LPL基因突变。在低LPL质量值的受试者中检测到Y 61 X、G188 E、D204 E、Int 3 -3' c（-6）t、G154 V、G105 R、Int 8 -5' t（2）c突变。这些错义突变被证实导致COS-1在体外表达系统中产生无功能的LPL。由于Int 3 -3' c（-6）t突变体在体内外均无异常剪接产物，该突变体可能与另一个导致LPL缺陷的突变体有关。Int 8 -5' t（2）c突变导致利用外显子8中的隐蔽5'供体剪接位点作为选择性剪接位点，跳过外显子8的134-bp片段。这些技术的发展和改进，以及LPL突变的积累将有助于LPL基因诊断，使预防高脂血症的个体方法成为可能。少

The aim of this study is to establish individual methods of prevention for life-style-related diseases, especially hypertriglyceridemia as a model case, because we think it is practical to focus on an individual genetical weakness for prevention against life-style-related diseases. We have elucidated etiology of primary type IV hyperlipidemia is a genetic background of heterozygous lipoprotein lipase (LPL) deficiency and superimposing triglyceride synthesis-stimulating factor on its genetic background. It means a LPL heterozygous deficient person without triglyceride synthesis-stimulating factor doesn't manifest hypertriglyceridemia. Individuals with heterozygous LPL deficiency have to be more carefully of superimposition of triglyceride synthesis-stimulating factor, alcohol drinking for example, than persons with two alleles of a normal LPL gene. The reliable and accurate genetic diagnosis of heterozygous LPL aberration is needed for development of individual methods of prevention for … More hypertiglyceridemia. We developed and improved LPL and hepatic triglyceride lipase mass measurement methods, direct sequencing of LPL gene, PCR method which didn't overlook mutations, and hypertriglyceride-induced atherogenic small dense LDL detection method. On the basis of these developments, we accumulated LPL gene mutations in Japanese. From the subjects with low LPL mass values, Y61X, G188E, D204E, Int3-3' c(-6)t, G154V, G105R, Int8-5' t(2)c mutations were detected. These missense mutations were confirmed to lead non-functional LPL production with COS-1 in vitro-expression system. As the Int3-3' c(-6)t mutation didn't have an aberrant splicing product in vivo and in vitro, this mutation seemed to link to another mutation which led to LPL deficiency. The Int8-5' t(2)c mutation led to the utilization of a cryptic 5' donor splice site in exon8 as an alternative splice site, skipping of a 134-bp fragment of exon8. These technical developments and improvements, and an accumulation of LPL mutations would contribute to LPL gene diagnosis that makes individual methods of prevention for hypertriglyceridemia possible. Less