人X染色体含有一个黑色素瘤抗原基因亚家族

肿瘤相关基因的研究是肿瘤基因形成学说的核心内容。肿瘤相关基因家族的研究则是其中的重点和难点，从4－6月孕龄人胎肝cDNA文库中克隆到一个黑色素瘤抗原基因亚家族，称为MAGE－D亚家族，其成员包括3个直系同源体（人MAGE－D1、大鼠SNERG－1和小鼠DLXIN－1）和2个旁系同源体（人MAGE－D和人KIAA1114）。该家族的3个人类成员均定位于染色体Xp11.21-p11.23，同时具有独特的基因组结构。分子进化树分析表明，该家族与已知MAGE－A、－B和－C3个亚家族之间具有明显的进化上分歧。该亚家族的发现为研究肿瘤相关基因新功能提供了重要线索。

A New Melanoma Antigen-ncoding Gene Subfamily in Human Chromosome X

A lot of studies have been focused on the tumor--related genes. We have cloned a new melanoma antigen--encoding gene (MAGE) from human fetal liver of third trimester and subsequently found that it represented a new MAGE gene subfamily, named MAGE--D The MAGE--D subfamily contained three orthologs including human MAGE--D1, rat SNERG-1 and mouse DLXIN-1, and two paralogs including human MAGE--D and human KIAA1114. All human members of MAGE--D subfamily are located in human chromosome Xp11.21--P11.23. Moreover, MAGE--D subfamily stands out from other known subfamilies MAGE--A, --B and --C of MAGE family in view of typical features such as exon / intron organization, absence of tumorspecific antigens, evolutionarily divergent in sequences. The identification of MAGE--D subfamily will be helpful in understanding the genesis of tumor.