Finnicum Casey T, Dolan Conor V, Willemsen Gonneke, Weber Zachary M, Petersen Jason L, Beck Jeffrey J, Codd Veryan, Boomsma Dorret I, Davies Gareth E, Ehli Erik A
Avera Institute for Human Genetics, Avera McKennan Hospital & University Health Center, Sioux Falls, South Dakota, United States of America.
Department of Biological Psychology, Vrije Universiteit, Amsterdam, The Netherlands.
PLoS One. 2017 Jan 26;12(1):e0170765. doi: 10.1371/journal.pone.0170765. eCollection 2017.
Telomere length has garnered interest due to the potential role it may play as a biomarker for the cellular aging process. Telomere measurements obtained from blood-derived DNA are often used in epidemiological studies. However, the invasive nature of blood draws severely limits sample collection, particularly with children. Buccal cells are commonly sampled for DNA isolation and thus may present a non-invasive alternative for telomere measurement. Buccal and leukocyte derived DNA obtained from samples collected at the same time period were analyzed for telomere repeat mass (TRM). TRM was measured in buccal-derived DNA samples from individuals for whom previous TRM data from blood samples existed. TRM measurement was performed by qPCR and was normalized to the single copy 36B4 gene relative to a reference DNA sample (K562). Correlations between TRM from blood and buccal DNA were obtained and also between the same blood DNA samples measured in separate laboratories. Using the classical twin design, TRM heritability was estimated (N = 1892, MZ = 1044, DZ = 775). Buccal samples measured for TRM showed a significant correlation with the blood-1 (R = 0.39, p < 0.01) and blood-2 (R = 0.36, p < 0.01) samples. Sex and age effects were observed within the buccal samples as is the norm within blood-derived DNA. The buccal, blood-1, and blood-2 measurements generated heritability estimates of 23.3%, 47.6% and 22.2%, respectively. Buccal derived DNA provides a valid source for the determination of TRM, paving the way for non-invasive projects, such as longitudinal studies in children.
由于端粒长度可能作为细胞衰老过程的生物标志物发挥潜在作用，它已引起了人们的关注。从血液来源的DNA中获得的端粒测量结果常用于流行病学研究。然而，采血的侵入性严重限制了样本采集，尤其是对于儿童。颊细胞通常用于DNA分离采样，因此可能是一种非侵入性的端粒测量替代方法。对在同一时间段采集的样本中获得的颊细胞和白细胞来源的DNA进行端粒重复序列质量（TRM）分析。对那些已有血液样本TRM数据的个体的颊细胞来源DNA样本进行TRM测量。通过定量聚合酶链反应（qPCR）进行TRM测量，并相对于参考DNA样本（K562）将其标准化为单拷贝36B4基因。获得了血液和颊细胞DNA的TRM之间的相关性，以及在不同实验室测量的相同血液DNA样本之间的相关性。采用经典双生子设计，估计了TRM的遗传力（N = 1892，同卵双生子 = 1044，异卵双生子 = 775）。测量TRM的颊细胞样本与血液样本1（R = 0.39，p < 0.01）和血液样本2（R = 0.36，p < 0.01）显示出显著相关性。在颊细胞样本中观察到了性别和年龄效应，这在血液来源的DNA中是常见的。颊细胞、血液样本1和血液样本2测量得出的遗传力估计值分别为23.3%、47.6%和22.2%。颊细胞来源的DNA为TRM的测定提供了一个有效的来源，为非侵入性项目（如儿童纵向研究）铺平了道路。
