Detecting non-multiplicative genotype relative risks from transmissions of parental alleles to affected children

The differential transmission of alleles from parents to affected children indicates that the locus under investigation is either directly involved in the occurrence of the disease or that there are allelic associations with other loci that are directly involved. Conditional logistic regression applied to a diallelic locus leads to a test with two degrees of freedom. The power of a single degree of freedom test to detect non-multiplicative allelic effects is discussed here.

Mapping quantitative trait loci for flag leave senescence as a yield determinant in winter wheat under optimal and drought stressed environments

The timing of flag leaf senescence (FLS) is an important determinant of yield under stress and optimal environments. A doubled haploid population derived from crossing the photo period-sensitive variety Beaver,with the photo period-insensitive variety Soissons, varied significantly for this trait, measured as the percent green flag leaf area remaining at 14 days and 35 days after anthesis. This trait also showed a significantly positive correlation with yield under variable environmental regimes. QTL analysis based on a genetic map derived from 48 doubled haploid lines using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers, revealed the genetic control of this trait. The coincidence of QTL for senescence on chromosomes 2B and 2D under drought-stressed and optimal environments, respectively, indicate a complex genetic mechanism of this trait involving the re-mobilisation of resources from the source to the sink during senescence.

Educational participation post-16: a longitudinal analysis of intentions and outcomes

The issue of levels of participation in post-compulsory education has been emphasised by the current policy initiatives to increase the age to which some form of participation is compulsory. One of the acknowledged weaknesses of research in the field of children's intentions with regard to participation is the lack of longitudinal data. This paper offers a longitudinal analysis using the Youth Survey from the British Household Panel Survey. The results show that most children can express intentions with regard to future participation very early in their secondary school careers and that these intentions are good predictors of actual behaviour five years later. Intentions to stay on are more consistent than intentions to leave and most children who finally leave at 16 have at some point said they want to remain in education post-16. The strongest association with participation levels is attainment at GCSE. However, there are also influences of gender and parental background and these remain, even after attainment is held constant. The results show the value of focusing on intentions for participation at a very early stage of children's school careers and also the importance of current attempts to reform curriculum and assessment for the 14-19 age group.

Parents' cognitions and expectations about their pre-school children: the contribution of parental anxiety and child anxiety

This study investigated the relative associations between parent and child anxiety and parents' cognitions about their children. One hundred and four parents of children aged 3-5 years completed questionnaires regarding their own anxiety level, their child's anxiety level and their cognitions about the child, specifically parents' expectations about child distress and avoidance, and parents' perceived control over child mood and behaviour. Both parent anxiety and parent report of child anxiety were significantly associated with parents' cognitions. Specifically, parent report of child anxiety correlated significantly with parent locus of control generally and, more specifically, with parental expectations and perceived control of child anxious mood and behaviour. Parent anxiety correlated significantly with locus of control and parents' expectations of child anxious mood and behaviour. Furthermore, when both child and parent anxiety were taken into account, only parental anxiety remained significantly associated with parental locus of control and perceived control of child anxious behaviour. For parents' perceived control of child anxious mood, only child anxiety remained significantly associated. The results suggest that parents' perceived control over their children's behaviour may primarily reflect parental anxiety, rather than child anxiety. Parental anxiety may, therefore, present an important target for interventions that aim to change parent's cognitions and behaviour.

Conversations around homework: links to parental mental health, family characteristics and child psychological functioning

Parents are increasingly expected to supplement their children's school-based learning by providing support for children's homework. However, parents' capacities to provide such support may vary and may be limited by the experience of depression. This may have implications for child development. In the course of a prospective, longitudinal study of children of postnatally depressed and healthy mothers, we observed mothers (N = 88) and fathers (N = 78) at home during maths homework interactions with their 8-year-old children. The quality of parental communication was rated and analysed in relation to child functioning. The quality of communication of each of the parents was related to their mental state, social class and IQ. While postnatal depression was not directly related to child development, there was some evidence of the influence of maternal depression occurring in the child's school years. Different aspects of parental communication with the child showed specific associations with different child outcomes, over and above the influence of family characteristics. In particular, child school attainment and IQ were associated with parental strategies to encourage representational thinking and mastery motivation, whereas child behavioural adjustment at school and self-esteem were linked to the degree of parental emotional support and low levels of coercion. Notably, the influence of maternal homework support was more strongly related to child outcome than was paternal support, a pattern reflected in mothers' greater involvement in children's schools and school-related activities. Some parents may need guidance in how to support their children's homework if it is to be of benefit to child functioning.

Discrepancy between parental reports of infants' receptive vocabulary and infants' behaviour in a preferential looking task

Two experiments are described which explore the relationship between parental reports of infants' receptive vocabularies at 1; 6 (Experiment 1a) or 1-3, 1;6 and 1;9 (Experiment 1b) and the comprehension infants demonstrated in a preferential looking task. The instrument used was the Oxford CD1, a British English adaptation of the MacArthur-Bates CD1 (Words & Gestures). Infants were shown pairs of images of familiar objects, either both name-known or both name-unknown according to their parent's responses on the CD1. At all ages, and on both name-known and name-unknown trials, preference for the target image increased significantly from baseline when infants heard the target's label. This discrepancy suggests that parental report underestimates infants' word knowledge.

The effects of maternal depression and parental conflict on children's peer play

Background Little is known about the relative effects of exposure to postnatal depression and parental conflict on the social functioning of school-aged children. This is, in part, because of a lack of specificity in the measurement of child and parental behaviour and a reliance on children's reports of their hypothetical responses to conflict in play. Methods In the course of a prospective longitudinal study of children of postnatally depressed and well women, 5-year-old children were videotaped at home with a friend in a naturalistic dressing-up play setting. As well as examining possible associations between the occurrence of postnatal depression and the quality of the children's interactions, we investigated the influence of parental conflict and co-operation, and the continuity of maternal depression. The quality of the current mother-child relationship was considered as a possible mediating factor. Results Exposure to postnatal depression was associated with increased likelihood, among boys, of displaying physical aggression in play with their friend. However, parental conflict mediated the effects of postnatal depression on active aggression during play, and was also associated with displays of autonomy and intense conflict. While there were no gender effects in terms of the degree or intensity of aggressive behaviours, girls were more likely to express aggression verbally using denigration and gloating whereas boys were more likely to display physical aggression via interpersonal and object struggles. Conclusions The study provided evidence for the specificity of effects, with strong links between parental and child peer conflict. These effects appear to arise from direct exposure to parental conflict, rather than indirectly, through mother-child interactions.

'They did not have a word': the parental quest to locate a 'true sex' for their intersex children

Given the paucity of research in this area, the primary aim of this study was to explore how parents of infants with unclear sex at birth made sense of 'intersex'. Qualitative methods were, used (semi-structured interviews, interpretative phenomenological analysis) with 10 parents to generate pertinent themes and provide ideas for further research. Our analysis highlights the fundamental shock engendered by the uncertain sex status of children, and documents parental struggles to negotiate a coherent sex identity for their children. Findings are discussed in light of the rigid two-sex system which pervades medicine and everyday life, and we argue that greater understanding of the complexity of sex and gender is required in order to facilitate better service provision and, ultimately, greater informed consent and parental participation regarding decisions about their children's status.