Brown Wendy E, Kesler Shelli R, Eliez Stephan, Warsofsky Ilana S, Haberecht Michael, Patwardhan Anil, Ross Judith L, Neely E Kirk, Zeng She Min, Yankowitz Jerome, Reiss Allan L
Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Road, Stanford, CA 94305-5719, USA.
Psychiatry Res. 2002 Dec 30;116(3):187-96. doi: 10.1016/s0925-4927(02)00086-0.
Turner syndrome (TS) results from the absence of an X chromosome in females. This genetic condition is associated with specific cognitive deficits and variations in brain volumes. The goal of this study was to use high-resolution magnetic resonance imaging (MRI) to determine morphological variations in TS and to investigate the effects of parental origin of the X chromosome on brain development in TS. MRI brain scans were acquired from 26 girls with TS and 26 age- and gender-matched controls. Seventeen of the TS subjects had a maternally inherited X chromosome (Xm), and nine of the subjects had a paternally inherited X chromosome (Xp). Rater-blind morphometric analyses were conducted to compare tissue volume differences between girls with TS and controls. Three-way analyses were used to compare subgroups and controls. Subjects with TS demonstrated bilateral decreases in parietal gray and occipital white matter accompanied by increased cerebellar gray matter. Subjects with Xm showed decreased occipital white matter and increased cerebellar gray matter compared to controls. No differences were found in comparisons between subjects with Xp and controls or between subjects with Xm and Xp. Results suggest that X monosomy affects posterior cerebral and cerebellar anatomy in TS. While differences between comparisons of Xm and Xp to controls might suggest an imprinting effect, no significant differences were found when the two subgroups were directly compared to each other. Further investigation into the possible role of genomic imprinting is therefore warranted.
特纳综合征（TS）是由于女性缺少一条X染色体所致。这种遗传状况与特定的认知缺陷和脑容量变化有关。本研究的目的是使用高分辨率磁共振成像（MRI）来确定TS患者的形态学变化，并研究X染色体的亲本来源对TS患者大脑发育的影响。对26名患有TS的女孩和26名年龄及性别匹配的对照者进行了脑部MRI扫描。其中17名TS患者的X染色体来自母亲（Xm），9名患者的X染色体来自父亲（Xp）。进行了评分者盲态形态学分析，以比较TS女孩与对照者之间的组织体积差异。采用三因素分析来比较亚组与对照者。TS患者表现出双侧顶叶灰质和枕叶白质减少，同时小脑灰质增加。与对照者相比，Xm患者的枕叶白质减少，小脑灰质增加。Xp患者与对照者之间或Xm患者与Xp患者之间的比较未发现差异。结果表明，X单体性影响TS患者大脑后部和小脑的解剖结构。虽然Xm和Xp与对照者比较的差异可能提示印记效应，但当直接比较这两个亚组时未发现显著差异。因此，有必要进一步研究基因组印记可能发挥的作用。
