Heritability of cognitive functions in nuclear families with bipolar I disorder / 中国神经精神疾病杂志

Objective To examine the heritability of neurocognitive functions in bipolar I disorder(BD-I)families and BD-associated cognitive endophenotypes. Methods Seventy-nine nuclear families consisting of euthymic BD-I probands and their healthy parents were recruited. Cognitive functions including attention, working memory, processing speed and executive function were evaluated by 7 classic neurocognitive tests, and the heritability of neuroconitive functions in these families was estimated using parent-offspring regression indexes of quantitative traits.Furthermore,the heritable cognitions were compared between 79 BD probands and 140 normal controls. Results After adjusted by age and education,mistake numbers of Trail Making Test A(TMT-A),total score and completed mission numbers of Tower of Hanoi (TOH) were significantly heritable (P<0.05). The comparison of these heritable cognitions between patients and normal controls showed that TOH total score and TOH completed mission numbers were significantly impaired in the patient group (P<0.05). Conclusion Processing speed and executive function are probably heritable in BD nuclear families. Executive function impairments may be disease-related which could be candidate endophenotypes for bipolar disorder.

The cognitive impairments of euthymic patients with early-onset or late-onset bipolar Ⅰ disorder / 中国神经精神疾病杂志

Objective To explore the characteristics of cognitive impairments in euthymic patients with early-on?set or late-onset bipolar I disorder (BD-I). Methods Ninety-four with onset age less than 21 (early onset group), 41 eu?thymic patients with onset age above 35 (late onset group) and 135 normal controls with matched education and age were enrolled. Seven classical neuropsychological tests were used to assess attention, processing speed, working memory and executive functions. Results The early-onset group was significantly worse than its corresponding normal controls in 14 indexes of all tests, including digital symbol, digital span, visual graphic reproduction (c1 and c2), time of TMT-A and TMT-B, verbal fluency, number of sorting, error and preserved error in WCST, as well as total score, completed missions, planning time and executing time in TOH (P<0.05). Moreover the effect size of difference were more than 0.4 in verbal fluency, time of TMT-A and TMT-B, and executing time in TOH. Compared with its matched control group, the late-on?set group was significantly impaired in 9 indexes, including digital span, visual graphic reproduction (c1,c2 and total), time of TMT-A, number of error and preserved error in WCST, as well as total score and completed missions in TOH (P<0.05), merely two indexes of TOH with effect size more than 0.4, while the late-onset group was no significantly impaired in digital symbol, TMT-B and verbal fluency. Conclusions There are significant cognitive impairments in euthymic BD-I patients with no matter early-onset or late-onset. But it seems that the cognitive impairments in early-onset bipo?lar disorder are more extensive and serious.

Association study of LIS1 and TSNAX genes with bipolar disorder in Chinese Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of neural development-related genes LIS1and TSNAX with bipolar disorder in a Chinese Han population.</p><p><b>METHODS</b>Three hundred and eight five patients (including 188 males and 197 females) from Guangzhou Brain Hospital with bipolar disorder meeting the Diagnostic and Statistic Manual of Bipolar Disorder (BDI) (Fourth Edition) criteria and 475 healthy controls from the local community were recruited. Ten single nucleotide polymorphisms (SNPs) of the LIS1 and TSNAX genes were genotyped by GoldenGate genotyping assay on an Illumina Beadstation 500 machine. Association analyses of SNPs and haplotypes were performed with Plink 1.07 software.</p><p><b>RESULTS</b>Analysis of the total sample has failed to find any association of SNP or haplotype of the two genes with BDI (P> 0.05). When patients were divided into subgroups with or without psychotic symptom, no significant association of the two genes was found with psychotic BDI or non-psychotic BDI (P> 0.05). No significant association was found between any SNP and haplotype of two genes and female BDI or male BDI, nor were significant association found between age of onset and LIS1 and TSNAX gene polymorphisms.</p><p><b>CONCLUSION</b>Our results indicated that LIS1 and TSNAX genes are not associated with susceptibility to bipolar I disorder in Chinese Han population.</p>