A diagnostic study on cardiomyopathy by using DNA analysis in the autopsy cases of sudden death and its application to a medicolegal judgment

方法心源性猝死后2 4h内尸检，取血10ml，-80ﾟC冰冻，取左、右室各2块，用10%福尔马林溶液固定，取血标本解冻，用碘化钠法提取外周血白细胞DNA。用一组引物对人β-肌球蛋白重链基因外显子13进行了聚合酶链式反应。用Dde I限制性内切酶对扩增片段进行切割，并在10%的聚丙烯酰胺凝胶上室温运行。结果第一例(59岁男性)心脏重920g。其次，56岁男性心脏重590g。63岁男性心脏重700g。48岁男性心脏重530g。27岁男性心脏重450g。其中一例为920g，25岁男性为680g，48岁男性为400g，DNA分析鉴定出161个碱基片段，129个碱基片段。在对心脏的组织病理学研究中，我们发现了心肌的紊乱。

MethodsIn each case which was autopsied within 24 hours after sudden cardiac death, a 10 ml blood sample was freezed at -80ﾟC and two pieces of the left cardiac ventricle and two ones of the right ventricle were fixed in 10% formaline solution.A blod sample was defrosted and DNA was extracted from isolated nuclei of peripheral white cells by procedures of sodium iodide method. A PCR amplification of exons 13 in human beta-Myosin Heavy Chain gene was done by using a set of primers. PCR-amplified fragments were broken by Dde I restriction enzyme and resolved on a 10% polyacrylamide gel run at room temperature. The gel was stained with ethidium bromide and gel bands were identified under ultraviolet light.Each piece of the cardiac ventricle was stained with hematoxylin-eosin (H-E) and azan stains and examined histopathologically.ResultsIn the first case (59-year-old male), the heart weighed 920 g. Next, in the 56-year-old male, the heart weighed 590 g. In the 63-year-old male, the one did 700 g. In the 48-year-old male, the one did 530 g. In the 27-year-old male, the one did 450 g. In the 65-year-old male, the one did 920 g. In the 25-year-old male, the one did 680 g. In the 48-year-old male, the one did 400 g.In a DNA analysis, 161 basepair fragment was identified and 129 basepair fragment was not in each case. In histopathological study on the cardiac ventricles, we found myocardial disarray.