Human Handedness Psychosis Etiology Studies

97%的右撇子（RH）个体在大脑的左半球（主导）开发语音和语言处理，而“次要”半球控制情感行为。然而，这种相关性在LH（左撇子）个体中失败了; 70%的人是左脑主导型，30%是右脑主导型。惯用手与大脑侧化之间复杂的相关性的原因一直是大脑发育中未回答的关键问题。我们推测，一个假设的基因，RGHT，功能指定左脑优势，导致发展右手偏好。为了通过实验来验证这些想法，我们一直在收集特定家庭的血液样本和脸颊拭子，目的是对假设的RGHT基因进行遗传作图。我们已经收集了足够的样本，下一阶段是使用这些样本通过同胞配对方法进行映射。我们已经发表了我们的随机隐性模型，其中两个同系物上都有非功能性隐性等位基因的个体有50：50的机会成为RH或LH。最近，我们发现有趣的关联，手的使用偏好与顺时针和逆时针头皮发旋旋转。我们认为，个体与正确的基因是RH和发展顺时针发旋，但个体与隐性等位基因是50：50的发旋方向。我们以前提出，人脑和内脏器官的偏侧化可能是由体细胞链特异性印迹和选择性染色单体/链分离（SSIS）模型控制的。它预测了一种染色体特异性的、非随机的WW：CC分离现象，其中两个较老的包含“沃森”链的染色单体形成一对同源染色体，在有丝分裂中被递送到一个子细胞，而较老的包含“克里克”链的染色单体被递送到另一个子细胞。这被认为是细胞分化在有丝分裂中产生非等效子细胞的机制。我们现在已经确定了这种偏向性链分离现象在小鼠细胞中的存在。在涉及7号染色体分离的小鼠细胞中，ES和内胚层细胞谱系表现出非随机（例如，WW：CC）模式，神经外胚层细胞表现出相反的非随机模式（例如，WC：WC）或它们中的重组被限制在G1期，但胰腺、中胚层和心肌细胞遵循通常预期的随机分布模式。在今后的实验中，我们希望找到这种染色体的偏链分离机制，并确定其他染色体是否也受到细胞类型调节的分离过程。

Ninety-seven per cent of right-handed (RH) individuals develop speech and language processing in the left (dominant) hemisphere of the brain, while the "minor" hemisphere controls emotional behavior. However, this correlation fails in LH (left-handed) individuals; 70% are left-brain dominant and 30% are right-brain dominant. The reason for this complex correlation of handedness with brain lateralization has been the key unanswered question for brain development. We have speculated that a hypothetical gene, RGHT, functions to specify left-brain dominance resulting in developing the right-handed preference. To test these ideas experimentally, we have been collecting blood samples and cheek swabs from specific families with the aim to genetically map the hypothesized RGHT gene. We have collected enough samples and the next stage is to use these samples for mapping by the sib-pair method. We have published our random recessive model in which individuals with the nonfunctional recessive allele on both homologs have a 50:50 chance of either being RH or LH. Recently, we found interesting association of hand use preference with the clockwise vs. counterclockwise scalp hair-whorl rotation. We suggest that individuals with the right gene are RH and develop clockwise hair whorls, but individuals with the recessive allele are 50:50 in hair whorl orientation. We have previously proposed that human brain and visceral organs laterality might be controlled by the Somatic Strand-specific Imprinting and selective chromatid/strand Segregation (SSIS) model. It predicted a chromosome-specific, nonrandom WW:CC segregation phenomenon where both older "Watson" strand-containing chromatids form a homologous pair of chromosomes are delivered in mitosis to one daughter cell and the older "Crick" strand-containing chromatids are delivered to the other daughter cell. This was proposed as a mechanism for cellular differentiation to produce non-equivalent daughter cells in mitosis. We have now established the existance of such biased strand segregation phenomenon in mice cells. In mouse cells concerning chromosome 7 segregation, ES and endoderm cell lineages exhibit a nonrandom (e.g., WW:CC) pattern , neuroectoderm cells exhibit an opposite nonrandom pattern (e.g., WC:WC) or recombination in them is restricted to the G1-phase, but the pancreatic, mesoderm, and cardiomyocyte cells follow the usually expected random distribution mode. In future exaperiments we want to find the mechanism of biased strand segregation of this chromosoem and also we will determine whether other chromosomes are likewise subject to cell type regulated segregation process.