Large Sample Of Families Research Articles

Searching high and low: a review of the genetics of bipolar disorder.

To review the methodologies and findings in the genetics of bipolar disorder (BPD), and to suggest future directions for research. Reports of family, twin, adoption, linkage, association, cytogenetic, and animal model studies, and segregation analyses in English, were identified from multiple MEDLINE searches. Hand searches were carried out in bibliographies from review articles. Family, twin, and adoption studies have provided strong evidence for a genetic etiology in BPD. Early reports of linkage of BPD to DNA markers at several chromosomal sites have not proven robust, perhaps because of the complex nature of BPD inheritance. However, linkage findings in the 1990s, on chromosomes 18, 21q, 12q, and 4p, have provided leads that are being pursued through both genetic and physical mapping. No gene has yet been definitively implicated in BPD. Strategies for increasing the power to detect BPD genes include: (1) dividing the phenotype into genetically meaningful subtypes to decrease heterogeneity: and (2) ascertaining a very large family sample--a multicenter study now in progress will collect 700 bipolar I sibling pairs. BPD may result from several genes acting in concert so that new multilocus statistical methods could enhance the capacity to detect loci involved. Family-based association studies using a very large number of newly identified single nucleotide polymorphisms (SNPs) may allow for more efficient screening of the genome. As the Human Genome Project approaches its goal of isolating all genes by 2003, the data generated is likely to speed identification of candidate BPD genes.

Consumption Smoothing among Working-Class American Families before Social Insurance

This paper examines whether the saving decisions of a large sample of working-class American families around the turn of the twentieth century are consistent with consumption smoothing tendencies in the spirit of the permanent income hypothesis. We develop two econometric models to decompose reported annual incomes from micro-data into expected and unexpected components, then we estimate marginal propensities to save out of each component of income. The two methodologies deliver similar regression estimates and reveal empirical patterns consistent with those reported in other recent research based on quite different contemporary household data. Marginal propensities to save out of unexpected income shocks are large relative to propensities based on expected income movements, though the former lie much below one and the latter much above zero. While these data reject strict parameterizations of the permanent income hypothesis, we nonetheless conclude that families' saving decisions in the historical period look quite "modern."

Evaluation of linkage of bipolar affective disorder to chromosome 18 in a sample of 57 German families.

Previously reported linkage of bipolar affective disorder to DNA markers on chromosome 18 was reexamined in a large sample of German bipolar families. Twenty-three short tandem repeat markers were investigated in 57 families containing 103 individuals with bipolar I disorder (BPI), 26 with bipolar II disorder (BPII), nine with schizoaffective disorder of the bipolar type (SA/BP), and 38 individuals with recurrent unipolar depression (UPR). Evidence for linkage was tested with parametric and non-parametric methods under two definitions of the affected phenotype. Analysis of all 57 families revealed no robust evidence for linkage. Following previous reports we performed separate analyses after subdividing the families with respect to the sex of the transmitting parent. Fourteen families were classified as paternal and 12 families as maternal. In 31 families the parental lineage of transmission of the disease could not be determined ('either' families). Evidence for linkage was obtained for chromosomal region 18p11.2 in the paternal families and for 18q22-23 in the 'either' families. The findings on 18p11.2 and 18q22-23 support prior evidence for susceptibility loci in these regions. The parent-of-origin effect on 18p11.2 is confirmed in our sample. The delineation of characteristics of 'either' families requires further study.

Evidence of Linkage to 6p23 and Genetic Heterogeneity in Nonsyndromic Cleft Lip with or without Cleft Palate

Nonsyndromic cleft lip with or without cleft palate (CL±P) is a congenital orofacial anomaly that derives from an embryopathy with failure of nasal process and palatal shelves fusion. CL±P is one of the most common malformations, affecting 1/700–1/1000 live births among Caucasians. Early investigations have suggested that a clefting gene may be located on the short arm of chromosome 6 (6p), as well as in other regions. In this study, we analyzed a large sample of families by using eight PCR markers that map on chromosome region 6p23–p24. The admixture test, as implemented in the HOMOG program, was significant when tested against multipoint data (α = 0.60,Pvalue 0.00004); the lod score calculated, assuming heterogeneity, was 3.60 at 1 cM telomeric to D6S259. Taken together these data demonstrate the presence of a locus for CL±P in the 6p23 chromosome region.

Human GABA, Receptor αl and α3 Subunits Genes and Alcoholism.

γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain. GABA effects are largely mediated by binding to the postsynaptic GABAA receptor, causing the opening of an integral chloride-ion channel. The GABAA antagonists picrotoxin and bicuculline reduce some ethanol-induced behaviors, such as motor impairment, sedation, and hypnosis. The role of this receptor in alcoholism is further supported by effective alleviation of alcohol withdrawal symptoms by GABAA agonists. To determine the role of the GABA, receptor (GABR) genes in the development of alcoholism, we have used α1 and α3 simple sequence repeat polymorphisms in a sample of unrelated alcoholics, alcoholic probands with both parents, and psychiatrically normal controls. For the GABRα1 gene, the differences between allele frequencies, when all alleles were compared together, were not significant between total alcoholics, subtypes of alcoholics, and normal controls. However, for GABRα3 , the differences between total alcoholics and normal controls were significant when all alleles were compared together. The differences between subtypes of alcoholics and normal controls were not significant. The results of haplotype relative risk analysis for both genes, GABRα1 and GABRα3 , were also negative. It is possible that the sample size in the haplotype relative risk is too small to have power to detect the differences in transmitted versus nontransmitted alleles. There is a need for a replication study in a large family sample, that will allow haplotype relative risk or affected sib-pair analysis.

Assessment of family relationship characteristics: A measure to explain risk for antisocial behavior and depression among urban youth.

Two large samples of urban families were used to develop and cross-validate an assessment model and a measure to tap basic family processes and risk among diverse ethnic groups. Six scales (Cohesion, Beliefs About Family, Deviant Beliefs, Organization, Support, and Communication) produced a 3-dimension higher order factor model (Cohesion, Structure, and Beliefs). Tests support reliance on composite family scoring. Most scales and each higher order factor relate to depression, and aggression. Relations vary little by age, ethnicity, marital status of parent, or family income. Implications for family assessment methodology and risk models are discussed.

HOW MOTHERS AND FATHERS VIEW PROFESSIONAL CAREGMNG FOR CHILDREN WITH DISABILITIES

The authors compared mothers' and fathers' perceptions of professional caregiving, using the MPOC, a self-administered questionnaire for parents. The authors looked at the aspects of caregiving 128 couples judged to be important, their perceptions of the actual caregiving received from health professionals and their stress. The data, from a relatively large sample of intact families, indicated that there were more similarities than differences between the mothers' and fathers' replies. Both valued the enabling and partnership aspect of caregiving most highly. Only one difference in reported experience was found: mothers reported experiencing significantly more coordinated and comprehensive care than did their spouses. The clinical implications of the findings are discussed, particularly with respect to the involvement of fathers in clinical intervention, and the belief that fathers are uninterested in their children's care.

THE ROLE OF TIME FRAME IN THE ASSESSMENT OF FAMILY FUNCTIONING

The purpose of this study was to evaluate how the stated time frame of family questionnaires can influence the individual's report of family events and relationships. Three whole‐family assessment procedures were administered to a large sample of intact families under two conditions—when the respondent was asked to describe his/her family “in general” and “during the past week”. Major findings indicated that (a) reports of family relationships reflected the same overall evaluation regardless of time frame, (b) the number or degree of positive endorsements was greater on the “in general” than the “past week” format, and (c) the impact of time frame varied greatly as a function of instrument. Explanations and implications of these findings are discussed.

Forest product use at an upper elevation village in Nepal

This paper describes forest product use at Chimkhola, an upper elevation village of west central Nepal. Villagers have large herds of livestock that they use to fertilize agricultural fields by holding the animals on cropland for one to several weeks prior to planting. Herds are moved sequentially from one group of fields to another until all are planted, and then families take animals into the forests. Herders, therefore, live in temporary shelters away from the homestead throughout the year, and for much of the year feed their livestock fodder cut from forest trees. By combining repeated interviews of sample households, one-time interviews with a large sample of village families, and direct measurements of forest products being used, I found that livestock maintenance consumes 74% of the hand-harvested wild biomass: 26.4% for green fodder, 32.3% for fuelwood at the herder's hut, and 13.8% for construction of the herder's hut. Fuelwood burned at the homestead is the next largest consumer, 17.6%. Villagers also use small amounts of forest materials for house construction, charcoal, agricultural implements, and bamboo for baskets and mats. The large amounts used by herders and livestock at Chimkhola mean that wild vegetation use there far exceeds the measurements made by previous reliable studies at other communities. This system of forest use is, however, degrading Chimkhola's forests and gradually converting them to shrublands.

Intensive family preservation services with abused and neglected children: An examination of group differences

Intensive Family Preservation Services (IFPS) have emerged as one of the most widely-employed placement prevention models in the field of Family-Based Services. Most IFPS evaluations have reported positive outcomes, but some results have been mixed. The use of heterogeneous client samples may explain some of the equivocal findings, so a study was designed to assess maltreatment group differences in a relatively large sample of families referred by Child Protective Service (CPS) agencies. It was found that: (a) Neglectful families, in contrast to abusive ones, were poorer, more reliant on public income, more likely to be headed by a single parent, had more children at imminent risk of placement, and were more likely to have medical, mental health, and substance abuse problems; (b) families referred for both abuse and neglect were more similar to the neglect-only group than the abuse-only one; and (c) although the majority of all children avoided placement, children from neglectful families were almost twice as likely to be placed than children from abusive ones, with those from multiple maltreatment families being at highest risk. The implications for research methodology and service delivery are discussed.

Families of Children with Disabilities: Normative Data and Other Considerations on Parenting Stress

The parenting stress of families who have a child with a disability is an area receiving considerable research. The present study used a family strengths or “normality” perspective to investigate three issues regarding parent-related and child-related parenting stress, as measured by the Parenting Stress Index (PSI) (Abidin, 1990). A large sample ( n = 725) of families who had a young child with disabilities participated. A comparison of parent-related and child-related parenting stress between the sample of families with a child with disabilities and the PSI normative sample was conducted. The distribution of PSI scores for the sample of families of children with disabilities was examined for statistical normality, and normative data for these families were presented. An item analysis was conducted on child-related parenting stress to examine issues regarding its construct validity for families of children with disabilities. Issues regarding the use of stress measures and to the construct of child-related stress as these impact on early intervention activities are discussed.

Sensitivity of transmission probabilities to paternity exclusion in segregation analysis.

Paternity exclusions are known to be common in Western countries and are yet neglected in segregation analysis because it is almost impossible to check it systematically on a large family sample. We had the opportunity of observing the sensitivity of segregation analysis parameters to a paternity exclusion in analyzing 34 families for a simple Mendelian trait, the acetylator phenotype. We found that only one family, with proven paternity exclusion, was responsible for a strong rejection of Mendelian transmission probabilities (P much much less than 0.001).

Transmission of symptoms of anxiety and depression in nuclear families

Anxiety and depression symptom scores from the SCL-90 questionnaire were observed in a large sample of nuclear families, and the effects of genes or family environment were estimated. Assuming no environmental transmission from parents to offspring, heritability was estimated at 0.43 for both anxiety and depression scores, and common sibling environment or reciprocal sibling influence explained 19% of the variances for both scores. Most of the (genetic or environmental) family effect seemed to be common for the two scores. There was no evidence of common determinants in the family for the symptom scores and alcohol consumption, not even of any substantial relationship within persons between symptoms and consumption. The spouse correlations were 0.25 for anxiety and 0.38 for depression. Similar values for the correlations between anxiety in one person and depression in his/her spouse implies a mate selection based on a single latent variable to which the two observed traits contribute.

Investigation of the twinning rate in families with the fragile X syndrome.

An excess of twins in families with the Martin-Bell or fra(X) syndrome was noted previously in one family study [Fryns, 1986]. We tried to confirm this observation in a second large sample of families from a different population. We calculated the number of twin births among the total number of live births of known obligate carriers found in fra(X) families ascertained in New South Wales, Australia. We only included births of known sex and excluded triplets. There were 5 male pairs, 3 female pairs and 9 unlike sex pairs of twins born among 752 live births. Thus the twining rate was 1/44 per live birth. We compared this rate to that found in two different types of individuals: 1) the rate of 1/96 which was obtained from the 1985 vital statistics for New South Wales, and 2) the rate 1/75 obtained from a sample of live births of obligate carriers with hemophilia A. The increase in twinning among heterozygotes with the fra(X) was highly significant when compared to the census data (p less than 0.001). However, it was not significantly different from that in the hemophilia data (p less than 0.05) which were collected in the same way as in the fra(X) families.

Comparison of inbred lines produced by single seed descent and pedigree inbreeding

Large random samples of inbred families extracted from the highly heterotic cross of varieties 2 and 12 of Nicotiana rustica by single seed descent (60 families) and pedigree inbreeding (784 families) have been compared for seven quantitative characters. As expected on theoretical grounds there were no differences in the phenotypic and genotypic properties of the inbred families ascribable to the method used for their extraction. The samples confirmed that inbred families which outperform the heterotic F1 can be readily extracted from it by either method. The hierarchical structure of the pedigree inbred families allowed a more sophisticated genetical analysis than the simple structure of the single seed descent families. But while the more complex structure allowed the detection of repulsion linkage for five of the seven characters, non-allelic interaction was detected for only one of them. The pedigree inbred families do not, therefore, provide a sensitive test for the non-allelic interactions which are detected by analyses of alternative designs.

Housing Pathways and Stratification: a study of life chances in the housing market

AbstractHousing research has yet to achieve an adequate framework to guide research into the effects of social policy. Two concepts are outlined and used in this article to analyse one local housing market; it is hoped that these will prove generally useful. The concepts are ‘housing status group’ (a modification of Rex and Moore's ‘housing classes’ model), and ‘housing pathway’, which refers to the structure of housing careers. In a low-cost study of a large sample of child-bearing families in Aberdeen, the relationship between housing tenure and occupational class, family size, and experience of housing deprivation is explored. Five principles of the local housing market's operation are abstracted by use of the status group approach, and three main housing pathways are identified. Data are presented which show that the chance of encountering bad housing conditions is strongly correlated with tenure, and that in turn, access to types of tenure is strictly rule-restricted. The local housing market appears to be rigidly stratified, with housing status groups re-inforcing other patterned social conditions, and housing pathways which are sharply differentiated. Because of this, the authors argue for a ‘constraint’ model of family housing experience which can be integrated into a general sociological theory of structured social inequality.

Economic class and access to physician services under public medical care insurance.

The dynamic effects of public medical care insurance on access to physician services are examined in this paper. A special definition of access is employed where access is measured as the inverse of the proportion of families of a given economic class who have not used physician services in a given year. Data are presented for the period 1963 through 1968 for a large sample of families in the Province of Saskatchewan in Canada. The evidence suggests that low-income classes have less contact with physicians than high-income classes. This disparity in accessibility is reduced, but not removed, as experience with Medicare increases. It is concluded that public medical care insurance does result in increased relative accessibility to physicians for the low-income classes.

A note on the occurrence of single-sex sibships.

SummaryA large sample of families drawn from the general population was found to contain an unexpectedly large number of all‐male sibships. This did not seem to be compatible with the hypothesis that sex is always determined by chance, but was in accord with the finding of an earlier study (Ounstead, 1953) based on selected families containing children with convulsive disorders.