Clinical and molecular studies on in born errors of ketone body metabolism

具有“轻度”突变的SCOT缺陷患者：我们在临床和分子水平上分析了3个具有SCOT缺陷患者的日本家族。我们发现，SCOT缺陷患者的“轻度”突变不显示特异性永久酮症。这表明，如果患者没有永久性酮症，我们不能排除SCOT缺陷（已提交）。T2缺陷中起始甲硫氨酸密码子突变的表征：我们在GK 30中鉴定了异源的起始密码子突变c.2T>C（另一个突变是149 delC）。我们为9个可能的错义突变的起始密码子的表达载体，并分析了翻译起始的效率在突变的起始密码子。虽然突变的效率是可变的，但所有突变的起始甲硫氨酸密码子都起起始密码子的作用。因此，我们得出结论，起始密码子突变导致T2缺陷的“轻度”突变（2003）。 ...更多信息 有“轻度”突变的耳鼻喉科患者：我们分析了5例日本T2缺陷患者的表型/基因型相关性，揭示了有“轻度”突变的T2缺陷患者的特征。我们发现在酮症酸中毒危象的频率和严重程度上，“轻度”和“重度”突变患者之间没有显著差异。然而，在非发作性条件下，尿有机酸和血液酰基肉毒碱谱的异常在具有“轻度”突变的患者中是微妙的，并且如果在非发作性条件下进行这些分析，则它们可能被遗漏为正常（2003）。我们还提出了一种可能性，即有“轻度”突变的患者通过与tyglyl-CoA的联合检测被误诊为正常（已提交）SCOT，3 HBD基因敲除小鼠：我们克隆了构建敲除小鼠所需的基因组片段，目前仍在构建中。2-甲基-3-羟基丁酸脱氢酶缺乏症酶法的建立及其临床分析：建立了以成纤维细胞和淋巴细胞为底物的酶活性测定方法。我们没有发现这种酶的缺陷，在细胞系，以前排除了T2缺乏症。少

SCOT deficient patients with "mild" mutation : We analyzed 3 Japanese families with SCOT deficient patients at the clinical and molecular level. We disclosed that SCOT deficient patients with "mild" mutations do not show a pathognomonic permanent ketosis. This indicates that we can not exclude SCOT deficiency if patients do not have permanent ketosis (Submitted).Characterization of mutations at the initiator methionine codon in T2 deficiency : We identified an initiator codon mutation, c.2T>C, heterozygously in GK30 (The other mutation was 149delC). We made expression vectors for 9 possible missense mutations at the initiator codon and analyzed the efficiency of translation initiation at the mutant initiator codons. Although the efficiencies were variable among the mutations, all the mutant initiator methionine codons were functioned as the initiator codon. Hence we concluded that initiator codon mutations result in "mild" mutations in T2 deficiency (2003).Characterization of T2 defici … More ent patients with "mild" mutations : We analyzedphenotype/genotype correlation in 5 Japanese T2 deficient patients and revealed characters for T2 deficient patients with "mild" mutations. We found no significant differences in the frequency and severity of ketoacidotic crises between patients "mild" and "severe" mutations. However, during non-episodic condition, abnormalities in urinary organic acid and blood acylcarnitine profiles was subtle in patients with "mild" mutations and they, can be missed as normal if these analyses are performed during non-episodic condition (2003). We also raised a possibility that patients with "mild" mutations were mis-diagnosed as normal by a coupled assay with tyglyl-CoA (submitted)SCOT, 3HBD knockout mice : We cloned genomic fragments necessary for construction of knockout constracts and are still making constructs.Establishment of enzyme assay for 2-methyl-3-hydroxybutyrate dehydrogenase deficiency and its clinical analysis : We established enzyme assay method for this enzyme using fibroblasts and lymphocytes. We did not find this enzyme defect in cell lines which were previously ruled out T2 deficiency. Less