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Phenovariance may be obscured when genetic mapping is performed using highly divergent strains, and closely similar strains are preferred if adequate marker density can be established. We sequenced the C57BL/10J mouse genome using the Applied Biosystems SOLiD platform and here describe a genome-wide panel of informative markers that permits the mapping of mutations induced on the closely related C57BL/6J background by outcrossing to C57BL/10J, and backcrossing or intercrossing. The panel consists of 127 single nucleotide polymorphisms validated by capillary sequencing: 124 spaced at ∼20-Mb intervals across the 19 autosomes, and three markers on the X chromosome. We determined the genetic relationship between four C57BL-derived substrains and used the panel to map two N-ethyl-N-nitrosourea (ENU)-induced mutations responsible for visible phenotypes in C57BL/6J mice through bulk segregation analysis. Capillary sequencing, with computation of relative chromatogram peak heights, was used to determine the proportion of alleles from each strain at each marker.

Context: Polycystic ovary syndrome (PCOS) is a common endocrinopathy of uncertain etiology but with strong evidence for a genetic contribution., Objective: The objective of the study was to test the hypothesis that the typical polycystic ovarian morphology is a marker of inherited biochemical features in families of women with PCOS., Design: A study of probands with PCOS and their sisters., Patients: Patients included 125 probands and 214 sisters. All probands had PCOS, defined by symptoms of anovulation and/or hyperandrogenism with polycystic ovaries on ultrasound. Affected sisters were defined by polycystic ovaries, regardless of symptoms, and unaffected sisters defined by normal ovarian morphology., Setting: This was a clinic-based study., Main Outcome Measures: Clinical, endocrine, and metabolic features in the various groups were compared, and estimates of broad-sense heritability were obtained using the quantitative transmission disequilibrium test., Results: Although affected sisters had fewer symptoms than probands (30% had no symptoms of PCOS), serum testosterone, androstenedione, LH, and fasting insulin and insulin sensitivity were similar in the two groups with polycystic ovaries but significantly different from those in unaffected sisters or controls. We observed moderate to high heritabilities for all traits studied in affected sister pairs, whereas heritabilities calculated from discordant siblings were substantially lower., Conclusions: These data provide further evidence for a genetic basis of PCOS. The high heritability of biochemical features in probands and affected sisters, despite wide variation in symptoms, shows that not only are these biochemical traits strongly influenced by genetic factors but also, importantly, that polycystic ovarian morphology is an index of inherited traits in families with PCOS.

Summary: Traditional two-dimensional (2D) software programs for drawing pedigrees are limited when dealing with extended pedigrees. In successive generations, the number of individuals grows exponentially, leading to an unworkable amount of space required in the horizontal direction for 2D displays. In addition, it is not always possible to place closely related individuals near each other due to the lack of space in 2Ds. To address these issues we have developed three-dimensional (3D) pedigree drawing techniques to enable clearer visualization of extended pedigrees. Currently no other methods are available for displaying extended pedigrees in 3Ds. We have made freely available a software tool--'Celestial3D'--that implements these novel techniques., Availability: Freely available to non-commercial users.

Context: Recently, a quantitative trait locus for stature was reported on chromosome 3p26 in patients with type 2 diabetes., Objective: Given that ghrelin is a peptide involved in GH release and located on 3p26, we hypothesized that variation within its gene (GHRL) may be responsible for the quantitative trait locus on 3p26., Design: The evidence for linkage around GHRL was refined with the genotyping of an additional four microsatellites (D3S4545, D3S1537, D3S1597, and D3S3611), giving a total of 27 markers, followed by multipoint variance components linkage analysis. Probands from the linkage families were typed for five common single nucleotide polymorphisms (SNPs) within GHRL and tested for association with adult stature using haplotype trend regression., Results: The maximum multipoint evidence for linkage between adult stature and the 27 microsatellites yielded an LOD score of 2.58 (P = 0.0003) between D3S1297 and D3S1304. Five common (frequency of > or =5%) SNPs were typed in the probands [two promoter SNPs (rs27647 and rs26802), two exonic (rs696217 and rs4684677), and one intronic (rs35683)] capturing 80% of the total common variation in GHRL. No association was found between any SNP (or haplotypes thereof) and adult stature., Conclusion: Common genetic variation within GHRL is not responsible for variation in adult stature in this population.

The late teens is an important transitional period as adolescents move into new social worlds which support or challenge their smoking. This paper draws on research with 99 Scottish 16- to 19-year olds which explored their understanding of their smoking and attitudes towards quitting and cessation support. The study involved qualitative interviews mostly with friendship pairs. Interviewees also completed a brief smoking questionnaire. Most regarded themselves as smokers but few thought they were addicted. Many were interested in quitting but this was not a priority. Perceived barriers to quitting related primarily to habitual and social aspects of dependence including friends' smoking, the smoking culture at work or college, stress and boredom. Few were interested in nicotine replacement therapy or cessation services, which they felt belonged to the world of older addicted smokers. The most effective quitting strategy was thought to be will-power. Traditional cessation services are therefore in their current form unlikely to appeal to older adolescents. Services aimed at this age group need to be grounded in their understandings of smoking and the social factors which support smoking. Young smokers should also be helped to understand how support may increase quitting success and how encourage quitting before smoking becomes entrenched in their daily routines.

This paper draws upon qualitative research with 100 smokers (50 male and 50 female) in two Scottish areas of disadvantage to investigate their perceptions and experiences of quitting. The fieldwork took place between 1999 and 2000, with data collected through in-depth individual interviews and the completion of a smoking day grid. While many interviewees wanted to quit, they drew on their understandings of habit and addiction to illustrate the difficulties which quitting posed. Addiction was referenced through accounts of actual and anticipated unpleasant withdrawal symptoms, while accounts of the difficulties associated with quitting drew primarily upon habitual usage and routine aspects of their lives. Interviewees reported interacting frequently with other smokers. They also highlighted how stressful aspects of their lives perpetuated habitual smoking and prompted relapse following periods of cessation. Although the contexts inhabited by the interviewees were crucial in inhibiting successful quitting attempts, these factors acted in conjunction with and exacerbated feelings of physiological dependence on tobacco. Interviewees were sceptical about the effectiveness of nicotine replacement therapy (NRT) other than in the immediate or short term. For the most part, interviewees felt that NRT could not address aspects of their lives that appeared to support and sustain smoking in the long term. The paper concludes that in order to facilitate and sustain smoking cessation, tobacco control interventions need to tackle both nicotine addiction and the material circumstances experienced by disadvantaged smokers.

Variation within the calpain-10 gene (CAPN10) has been proposed to account for linkage to type 2 diabetes on chromosome 2q in Mexican-Americans, and associations with diabetes have been reported in several other populations. Given the epidemiological, physiological, and genetic overlap between type 2 diabetes and polycystic ovary syndrome (PCOS), CAPN10 represents a strong candidate gene for a role in PCOS susceptibility. Using both family based and case-control association resources (146 parent-offspring trios; 185 additional PCOS cases; 525 control subjects, all of European ancestry), we sought association between CAPN10 variation and PCOS, focusing on four single nucleotide polymorphism (SNP) variants (SNP-44, SNP-43; SNP-19; SNP-63). On single-locus transmission disequilibrium analysis in the 146 trios, there was nominal evidence (P = 0.03) of excess transmission of the more common allele at SNP-63. This association was not, however, replicated in the case-control analysis. No other significant associations were observed at the single-locus or haplotype level in either the transmission-disequilibrium or case-control analyses. The relative risk for the high-risk diabetes susceptibility 112/121 genotype (SNPs 43-19-63) was 0.84 (95% confidence intervals, 0.40-1.71). No associations were seen with intermediate traits of relevance to diabetes and PCOS pathogenesis. We have found no evidence from these analyses that CAPN10 gene variation influences susceptibility to PCOS.

Although it has been demonstrated that eukaryotic cellular origins of DNA replication may harbor stimulatory elements that bind transcription factors, how these factors stimulate origin function is unknown. In Saccharomyces cerevisiae , the transcription factor Abf1p stimulates origin function of ARS121 and ARS1 . In the results presented here, an analysis of Abf1p function has been carried out utilizing LexA(BD)-Abf1p fusion proteins and an ARS 121 derivative harboring LexA DNA-binding sites. A minimal region which stimulates origin function mapped to 50 amino acids within the C-terminus of Abf1p. When tested for transcriptional activation of a LacZ reporter gene, the same LexA(BD)-Abf1p fusion protein had negligible transcriptional activation potential. Therefore, stimulation of ARS 121 may occur independently of a transcriptional activation domain. It has been previously observed that the Gal4p, Rap1p DNA-binding sites and the LexA-Gal4p fusion protein can replace the role of Abf1p in stimulating ARS 1 . Here we show that the stimulatory function of Abf1p at ARS 121 cannot be replaced by these alternative DNA-binding sites and the potent chimeric transcriptional activator LexA(BD)-Gal4(AD)p . Hence, these results strongly suggest that the Abf1p stimulation of replication may differ for ARS 121 and ARS 1 , and imply specificity in the Abf1p/ARS 121 relationship.