Awasthi Gauri, Dash Aditya P, Das Aparup
Evolutionary Genomics & Bioinformatics Laboratory, National Institute of Malaria Research (ICMR) New Delhi, India.
Indian J Med Res. 2009 May;129(5):534-41.
BACKGROUND & OBJECTIVE: Understanding evolutionary genetic details of immune system genes responsible for infectious diseases is of prime importance concerning disease pathogenecity. Considering malaria as a devastating disease in the world including India, detail evolutionary understanding on human immune system gene is essential. The primary aim of this study was to initiate work on one such gene, the human CD36 gene responsible in malaria pathogenesis.
DNA sequences of the human CD36 gene was retrieved from public domain and fine-scale details were characterized. Both comparative and evolutionary analyses were performed with sequences from six other taxa (5 mammalian one avian) where CD36 homologs are present. Different statistical analyses were also performed.
Differential distribution in number and length of exons and introns was detected in CD36 gene across seven taxa. The CpG islands were also found to be distributed unevenly across the gene and taxa. Neighbour-joining tree was constructed and it was observed that the chimpanzee and human are diverged at the CD36 gene relatively recently. The chicken, Gallus gallus was found to be diverged from rest of the taxa significantly. Also copy number variation was observed across different taxa.
INTERPRETATION & CONCLUSION: Comparative genomic study of a human immune system gene CD36 show relationships among different taxa at the evolutionary level. The information can be of help to study genetic diversity in malaria endemic zones and to correlate it with malaria pathogenecity.
了解负责传染病的免疫系统基因的进化遗传细节对于疾病致病性至关重要。鉴于疟疾在包括印度在内的全球都是一种毁灭性疾病，深入了解人类免疫系统基因的进化情况至关重要。本研究的主要目的是启动对其中一个基因——参与疟疾发病机制的人类CD36基因的研究工作。
从公共数据库中检索人类CD36基因的DNA序列并对其精细细节进行表征。对存在CD36同源物的其他六个分类单元（5种哺乳动物和1种鸟类）的序列进行了比较和进化分析。还进行了不同的统计分析。
在七个分类单元的CD36基因中检测到外显子和内含子数量及长度的差异分布。还发现CpG岛在基因和分类单元中分布不均。构建了邻接树，观察到黑猩猩和人类在CD36基因上的分化相对较近。发现家鸡与其他分类单元有明显分化。不同分类单元之间也观察到拷贝数变异。
对人类免疫系统基因CD36的比较基因组研究揭示了不同分类单元在进化水平上的关系。这些信息有助于研究疟疾流行地区的遗传多样性，并将其与疟疾致病性相关联。
