尿酸是嘌呤代謝後的產物，主要在腎臟中被排泄掉，是評估人體腎功能的一個重要生化指標。研究顯示，血清尿酸值過高的人容易罹患痛風，在痛風患者關節中常發現的尿酸結晶是導致疼痛的原因，此外尿酸還與心血管疾病、肥胖、糖尿病、喝酒、抽菸有關。台灣的健康調查指出，大約每五個台灣成年男性就有一人罹患高尿酸血症(血清尿酸值大於7 ml/dl)，在成年女性中則是每十人就有一人罹患(血清尿酸值大於6 ml/dl)，與其他種族或國家作比較，我國國人罹患高尿酸血症的比例偏高。國內過去有針對單一基因與尿酸做關聯性分析的研究，然而以大量基因位點來做的研究仍有不足，因此本次研究透過台灣人體資料庫的資料來做尿酸的全基因體關聯性分析，探究哪些基因位點與血清尿酸值具有高度相關性。
研究上我們使用的資料包括年齡、性別、身高體重、血清尿酸值、問卷調查的抽菸狀況、飲酒狀況、心血管疾病、第二型糖尿病，以及單一核苷酸多態性的基因資料。關聯性分析所用的模型是加成模式線性迴歸模型。此外我們也分別針對男女做研究，嘗試了解男女之間影響尿酸的基因位點是否有差異。
研究結果顯示，總共有八個與血清尿酸值有顯著線性相關的位點被我們找到，其中文獻上從未發現的有兩個，分別是SLC2A9上的rs77140241與MUC1上的rs4072037。其他的位點包括ABCG2上的rs4148155、rs1001179、rs13144899，SLC2A9的rs3775948，GCKR上的rs780093與SLC17A3上的rs1165205。另外我們找到了只在台灣男性才顯著的新位點，基因SRPK2上的rs17721991。

Uric Acid (UA) is the end oxidation product of purine catabolism and would be excreted in kidney. Hence, UA is an important biomarker for estimating the kidney functions. It is reported that the patients with high level of serum UA (SUA) tend to suffer from gout. The physical pain usually results from the UA crystals in the patients’ joints. Furthermore, UA is also associated with cardiovascular diseases, obesity and diabetes. Drinking and smoking frequently affect the level of UA. According to a Taiwanese health survey, one fifth of males and one tenth of females in Taiwan have hyperuricemia (SUA > 7 ml/dl, SUA > 6 ml/dl, respectively). Also, the survey indicated the rates in Taiwan are higher than them in other populations. In some of literature, it is estimated that the heritability of UA is in the range of 40% to 73%. In Taiwan, the previous study mainly focused on the relation between a genetic locus and SUA. A more comprehensive genome-wide study is still lacking. Thus, the present study aims to discover the new loci related to SUA levels through genome-wide association study (GWAS) using the Taiwan biobank (TWB) data.
The TWB data we used in this study include age, gender, height, weight, SUA level, the state of cardiovascular diseases, diabetes, drinking, smoking and the genetic information (single nucleotide polymorphisms, SNPs). In the association study, we adopted the additive linear regression model. Besides, we divided the samples by the gender and conducted the association analysis to understand whether the loci related to SUA are different between males and females.
The results showed that 2 new genetic loci (rs77140241, rs4072037) are discovered in our study. We found the 6 known SUA-associated SNPs (rs4148155, rs3775948, rs10011796, rs13144899, rs780093, rs1165205). Besides, the SNP rs17721991 is a new discovered genetic locus associated with SUA only in male.

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