Fine mapping and characterisation of polymorphic immunoregulatory genes in the central MHC

主要组织相容性复合体（MHC）是一组基因，通常作为一个块遗传。这一组包括HLA基因，它可以作为邻近基因的标记，这些基因的特征不太明显。例如，HLA基因的一些变异形式（多态性）标志着对糖尿病、狼疮和IgA缺乏的易感性的差异。我们认为，这可能是由影响各种靶器官持续炎症控制的邻近非特征基因的变异引起的。迄今为止的证据表明，中央MHC中的一个基因可能是罪魁祸首。在这个项目中，我们将研究来自HLA和其他MHC基因不寻常组合的患者的DNA，以进一步确定MHC的哪一部分包含关键的免疫调节基因。人类基因组计划已经确定了MHC中的大多数基因，因此我们将能够在感兴趣的区域中选择最有希望的候选基因。然后，我们将使用已知HLA类型的DNA来确定候选基因在个体之间是否存在差异。然后，通过创建携带部分反向（反义）方向基因的细胞系来研究感兴趣基因的功能。这产生了一个反向信使RNA (m)，它与正常的mRNA结合，阻止蛋白质的合成。然后，我们将检查产生的细胞系的哪些反应是异常的（例如：炎症介质或细胞因子的产生）。在阐明了我们基因的功能之后，我们将在培养的细胞中过度表达患者体内出现的每种版本，并寻找功能上的差异。与此同时，我们将使用具有已知MHC基因组合的实验室小鼠来确定特定基因对活体动物的影响。

The major histocompatibility complex (MHC) is a group of genes that is usually inherited as a block. The group includes the HLA genes which can serve as markers for neighbouring genes that are less well characterised. For example, some variant forms (polymorphisms) of the HLA genes mark differences in susceptibility to diabetes, lupus and IgA deficiency. We propose that this may be caused by variations in the neighbouring uncharacterised genes affecting control of persistent inflammation of various target organs. Evidence so far suggests a gene in the central MHC may be responsible. In this project we will study DNA from patients who have unusual combinations of HLA and other MHC genes, to further define which part of the MHC contains the critical immunoregulatory genes. Most genes in the MHC have now been identified by the Human Genome Project, so we will be able to select the most promising candidates in the region of interest. We will then use DNA of known HLA types to determine if the candidate genes vary between individuals. The function of interesting genes will then be investigated by creating cell lines carrying part of the gene in the reverse (anti-sense) orientation. This generates a reverse messenger (m) RNA which binds the normal mRNA and prevents synthesis of the protein. We will then examine which responses of the resultant cell lines are abnormal (eg: production of inflammatory mediators or cytokines). Having elucidated the functions our genes, we will overexpress each version that occurs in patients in cultured cells and look for differences in function. In parallel with this work, we will use laboratory mice with known combinations of MHC genes to establish the effects of particular genes in a live animal.