Peper Jiska S, Schnack Hugo G, Brouwer Rachel M, Van Baal G Caroline M, Pjetri Eneda, Székely Eszter, van Leeuwen Marieke, van den Berg Stéphanie M, Collins D Louis, Evans Alan C, Boomsma Dorret I, Kahn René S, Hulshoff Pol Hilleke E
Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center, Utrecht, The Netherlands.
Hum Brain Mapp. 2009 Jul;30(7):2184-96. doi: 10.1002/hbm.20660.
Puberty represents the phase of sexual maturity, signaling the change from childhood into adulthood. During childhood and adolescence, prominent changes take place in the brain. Recently, variation in frontal, temporal, and parietal areas was found to be under varying genetic control between 5 and 19 years of age. However, at the onset of puberty, the extent to which variation in brain structures is influenced by genetic factors (heritability) is not known. Moreover, whether a direct link between human pubertal development and brain structure exists has not been studied. Here, we studied the heritability of brain structures at 9 years of age in 107 monozygotic and dizygotic twin pairs (N = 210 individuals) using volumetric MRI and voxel-based morphometry. Children showing the first signs of secondary sexual characteristics (N = 47 individuals) were compared with children without these signs, based on Tanner-stages. High heritabilities of intracranial, total brain, cerebellum, and gray and white matter volumes (up to 91%) were found. Regionally, the posterior fronto-occipital, corpus callosum, and superior longitudinal fascicles (up to 93%), and the amygdala, superior frontal and middle temporal cortices (up to 83%) were significantly heritable. The onset of secondary sexual characteristics of puberty was associated with decreased frontal and parietal gray matter densities. Thus, in 9-year-old children, global brain volumes, white matter density in fronto-occipital and superior longitudinal fascicles, and gray matter density of (pre-)frontal and temporal areas are highly heritable. Pubertal development may be directly involved in the decreases in gray matter areas that accompany the transition of our brains from childhood into adulthood.
青春期代表着性成熟阶段，标志着从儿童期向成年期的转变。在儿童期和青少年期，大脑会发生显著变化。最近发现，5至19岁之间额叶、颞叶和顶叶区域的变异受不同基因控制。然而，在青春期开始时，脑结构变异受遗传因素（遗传率）影响的程度尚不清楚。此外，人类青春期发育与脑结构之间是否存在直接联系尚未得到研究。在此，我们使用容积磁共振成像和基于体素的形态测量法，对107对同卵和异卵双胞胎（N = 210人）9岁时的脑结构遗传率进行了研究。根据坦纳分期，将出现第二性征初现迹象的儿童（N = 47人）与未出现这些迹象的儿童进行比较。结果发现，颅内、全脑、小脑以及灰质和白质体积的遗传率较高（高达91%）。在区域上，后额枕叶、胼胝体和上纵束（高达93%），以及杏仁核、额上回和颞中回皮质（高达83%）具有显著遗传性。青春期第二性征的初现与额叶和顶叶灰质密度降低有关。因此，在9岁儿童中，全脑体积、额枕叶和上纵束的白质密度以及（额）额叶和颞叶区域的灰质密度具有高度遗传性。青春期发育可能直接参与了大脑从儿童期向成年期转变过程中灰质区域的减少。
