Ponnusamy Vinithra, Subramanian Gowtham, Vasanthakumar Keerthana, Muthuswamy Karthi, Panneerselvan Prabha, Krishnan Vasanth, Subramaniam Selvakumar
Molecular Physiology Laboratory, Department of Biochemistry, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India.
Men's Health Research Unit, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
Hum Genet. 2025 Jan;144(1):15-30. doi: 10.1007/s00439-024-02690-1. Epub 2024 Aug 6.
Genetic variations in taste receptors are associated with gustatory perception and obesity, which in turn affects dietary preferences. Given the increasing tendency of people with obesity choosing sweet, high-fat meals, the current study assessed the cross-regulation of two polymorphisms of the sweet taste receptor (T1R2/T1R3), rs35874116 and rs307355, on fat sensitivity in Indian adults. We investigated the association between taste sensitivity and BMI in the T1R2, T1R3, and CD36 polymorphic and non-polymorphic groups. The general labelled magnitude scale (gLMS) was used to assess the taste sensitivity of 249 participants in addition to anthropometric data. TaqMan Probe-based RT-PCR was employed to determine the polymorphisms. Additionally, the colorimetric method utilizing 3, 5-dinitro salicylic acid was used to evaluate the participants' salivary amylase activity. The mean detection thresholds for linoleic acid (LA) and sucrose were greater in individuals with obesity (i.e., 0.97 ± 0.08 mM and 0.22 ± 0.02 M, respectively) than in healthy adults (p < 0.0001), indicating lower sensitivity. Moreover, it was found that a greater proportion of persons with obesity fall into the polymorphic groups (i.e., 52% with genotype CD36 AA, 44% with genotype T1R2 CC, and 40% with genotype T1R3 TT). All three single nucleotide polymorphisms support the Hardy-Weinberg equilibrium (p = 0.78). The Pearson correlation analysis between LA and the sucrose detection threshold revealed a significant (p < 0.0001) positive relationship with an r value of 0.5299. Moreover, salivary amylase activity was significantly (p < 0.05) higher in the polymorphic sub-groups. The results of our study imply that genetic variations in T1R2/T1R3 receptors affect perception of both sweetness and fat, which may have an effect on obesity.
味觉受体的基因变异与味觉感知及肥胖有关，而这反过来又会影响饮食偏好。鉴于肥胖人群选择高糖、高脂食物的趋势日益增加，本研究评估了甜味受体（T1R2/T1R3）的两种多态性rs35874116和rs307355对印度成年人脂肪敏感性的交叉调节作用。我们调查了T1R2、T1R3和CD36多态性及非多态性组中味觉敏感性与体重指数之间的关联。除人体测量数据外，还使用通用标记量值量表（gLMS）评估了249名参与者的味觉敏感性。采用基于TaqMan探针的RT-PCR来确定多态性。此外，利用3,5-二硝基水杨酸的比色法用于评估参与者的唾液淀粉酶活性。肥胖个体中亚油酸（LA）和蔗糖的平均检测阈值（分别为0.97±0.08 mM和0.22±0.02 M）高于健康成年人（p<0.0001），表明敏感性较低。此外，发现肥胖人群中多态性组的比例更高（即基因型为CD36 AA的占52%，基因型为T1R2 CC的占44%，基因型为T1R3 TT的占40%）。所有三个单核苷酸多态性均符合哈迪-温伯格平衡（p = 0.78）。LA与蔗糖检测阈值之间的Pearson相关分析显示存在显著的正相关（p<0.0001），r值为0.5299。此外，多态性子组中的唾液淀粉酶活性显著更高（p<0.05）。我们的研究结果表明，T1R2/T1R3受体的基因变异会影响甜味和脂肪的感知，这可能对肥胖产生影响。
