ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The ambiguous status of unipolar relatives in the pedigrees of bipolar probands has long plagued investigators, and may have contributed significantly to the difficulties replicating linkage findings for bipolar disorder. We present here a conceptual model, based on a selective review of family and course data, and use it to quantify this problem, concluding that 65–74% of the unipolar relatives of bipolars must be bipolar from the genetic point of view. We then offer a set of predictions for the characteristics of UP individuals who are “genetically bipolar”, and suggest that these characteristics should lead to differences between UP relatives of BPs and other UP groups. Such differences could then be combined to form a caseness index that would rank unipolar relatives by the chances that they are “genetically bipolar”, and could serve as Ott's measure of certainty that weights the contribution of individual unipolar relatives in a linkage analysis. We conclude with a review of the implications of this model for the unipolar-bipolar distinction and the potential benefits and limitations of this approach to classification in linkage analyses of bipolar and other psychiatric disorders.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Kendler (1990) suggests that the use of “super-normal” control groups will produce spurious false positive evidence for coaggregation. We amplify his analysis to indicate that analyses taking the subgroupings within the probands into account can deal with this problem. Further, such a “super-normal” control group may be more practical than the alternative method of representative sampling of probands and controls.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The protein-coding region of the beta-nerve growth factor (NGF) gene was analyzed in seven unrelated schizophrenic patients and six control subjects. This area contained the entire mature human beta-NGF polypeptide. The gene fragment was amplified from genomic DNA by the polymerase chain reaction and subcloned to isolate individual alleles. Automated fluorescent sequencing of the clones revealed no consistent pattern of errors which would indicate a genetic deficit in any of the individuals studied. Southern blotting was used to confirm that errors found in the clones by sequencing were not present in the original genomic DNA. The NGF molecule is thus not likely to be abnormal in the schizophrenics tested.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

We ascertained nine multigenerational pedigrees afflicted with multiple cases of schizophrenia. Alterations in dopaminergic neurotransmission have been implicated in the etiology of this disease and tyrosine hydroxylase (TH) is the rate limiting enzyme in the synthesis of dopamine. Because TH mutations might contribute to the pathogenesis of schizophrenia, we carried out a linkage analysis between schizophrenia in nine families and two RFLP probes that map to the TH gene region on the short arm of chromosome 11. Evidence of linkage was not found.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Two strains of inbred mice, C57BL/6J and DBA/2J, were tested for saccharin–morphine and saccharin–cocaine preference using a two-bottle, 24-h drug-control solution paradigm. Quinine–saccharin solutions were used to control for strain-related differences in preference for sweetened alkaloid solutions. The C57BL/6J mice consumed significantly more morphine than the DBA/2J mice and had higher cocaine preference scores. Morphine and cocaine preference scores of individual mice were significantly correlated in the C57BL/6J strain.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Ninety-three pairs of same-sex twins were examined at the age of 3 years and their mothers were interviewed to assess the twins' behaviours. Sixty-one pairs were followed up. The monozygotic twins were found to be significantly more concordant than the dizygotic with respect to reaction to sudden noises and absence of stranger anxiety in the first year of life, and in ability to sleep alone and clinging to the mother at 3 years. A significant difference in concordance was also found for abundant salivary drooling in infancy, motion sickness, constipation, perspiration and bedwetting at 3 years, and night terrors at 3 years or at follow-up.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Mean and maximum lod scores were generated by computer simulation methods (SIMLINK) to examine relative informativeness for linkage of 12 pedigrees with three-five affected members, assuming linkage of a rare (population allele frequency = 0.01) dominant disease allele to single and to flanking markers, with varying recombination fractions and numbers of marker alleles, and considering only affected individuals and parents when available. The simulated mean lod scores represent reasonable approximations of calculated expected lod (ELOD) scores. Also studied were sibships (two-four affected), effects of unavailability of one or both parents, and genotyping of additional well offspring to “reconstruct” the marker genotype of a deceased parent. These pedigree constellations provide significant linkage information, particularly with flanking markers at 5–11 cM intervals with PICs of at least 0.70, e.g. mean lod scores of 0.22–0.26 per informative meiosis (5 cM intervals, four equally frequent alleles per marker) for simple constellations. Pedigrees (with the same number of affected members) are more informative when the oldest available generation includes either a single ill progenitor (e.g. proband's parent or grandparent) or undiagnosed parents available for marker genotyping, rather than affected siblings (e.g. proband and a sibling, or proband's parent and uncle). On average, the availability of one parent for genotyping is almost as informative as two parents, and genotyping of two undiagnosed offspring can restore most of the information lost when one parent is unavailable. When parental marker genotypes are available, however, unaffected siblings provide little information when penetrance is estimated at 0.8 or less. An introduction to linkage information principles is provided, implications are discussed for prioritization of families for linkage studies, and relevance of the data for the study of more complex modes of inheritance is considered.

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID

ISSN:0955-8829    

出版商:OVID    

年代:1993

数据来源: OVID