[Evolution of dry eye disease diagnostics]

This article reviews modern functional and instrumental examination methods included in the diagnostic algorithm for dry eye disease. The described methods can serve as an objective criterion for the effectiveness of the therapy.

An Overview of the Genetics and Genomics of the Urochloa Species Most Commonly Used in Pastures

Pastures based on perennial monocotyledonous plants are the principal source of nutrition for ruminant livestock in tropical and subtropical areas across the globe. The Urochloa genus comprises important species used in pastures, and these mainly include Urochloa brizantha, Urochloa decumbens, Urochloa humidicola, and Urochloa ruziziensis. Despite their economic relevance, there is an absence of genomic-level information for these species, and this lack is mainly due to genomic complexity, including polyploidy, high heterozygosity, and genomes with a high repeat content, which hinders advances in molecular approaches to genetic improvement. Next-generation sequencing techniques have enabled the recent release of reference genomes, genetic linkage maps, and transcriptome sequences, and this information helps improve our understanding of the genetic architecture and molecular mechanisms involved in relevant traits, such as the apomictic reproductive mode. However, more concerted research efforts are still needed to characterize germplasm resources and identify molecular markers and genes associated with target traits. In addition, the implementation of genomic selection and gene editing is needed to reduce the breeding time and expenditure. In this review, we highlight the importance and characteristics of the four main species of Urochloa used in pastures and discuss the current findings from genetic and genomic studies and research gaps that should be addressed in future research.

Genetic Studies of Metabolic Syndrome in Arab Populations: A Systematic Review and Meta-Analysis

Background: The metabolic syndrome (MetS) is prevalent in Arabian populations. Several small-scale studies have been performed to investigate the genetic basis of MetS. This systematic review and meta-analysis aimed to examine whether candidate gene polymorphisms are associated with MetS susceptibility among ethnic groups of the Arabian world and to suggest possible directions for future research regarding genetic markers and MetS.

Methods: A search was conducted for peer-reviewed articles that examined the genetic association of MetS in Arabian populations in the following databases: Medline, Embase, Scopus, Direct Science, Web of Science, ProQuest, and Google Scholar until March 31, 2021. Articles were eligible if they were case-control studies, which investigated MetS as a dichotomous outcome (MetS vs no MetS). To assess the quality of the studies, the Q-Genie tool (Quality of Genetic Association Studies) was used. A non-central chi2 (random-effect) distribution was used to determine the heterogeneity (H) of Q and I (Galassi et al., The American journal of medicine, 2006, 119, 812–819) statistics.

Results: Our search strategy identified 36 studies that met our inclusion criteria. In most cases, studies were excluded due to a lack of statistical information such as odds ratios, confidence intervals, and p-values. According to the Q-Genie tool, 12 studies scored poorly (a score of≤35), 13 studies scored moderately ( >35 and≤45), and 12 studies had good quality ( >45 or higher). The most frequently studied genes were FTO and VDR (both included in four studies). Three SNPs indicated increased risk for MetS after calculating the pooled odds ratios: FTO-rs9939609 (odds ratio 1.49, 95% CI: 0.96–2.32); LEP-rs7799039 (odds ratio 1.85, 95% CI: 1.37–2.5); and SERPINA12-rs2236242 (odds ratio 1.65, 95% CI: 1.21–2.24). Meta-analysis studies showed no significant heterogeneity.

Conclusion: There were many sources of heterogeneity in the study settings. Most of the studies had low to moderate quality because of sample size and power issues, not considering all potential sources of bias, and not providing details about genotyping methods and results. As most studies were small-scale, aimed to replicate findings from other populations, we did not find any unique genetic association between MetS and Arabian populations.

Neurodegenerative Diseases: A Multidisciplinary Approach

The rapid pattern of population ageing in recent years increases the risk of appearance of associated neurodegenerative diseases. Dementias are one of the most feared disorders, and although not necessarily all elderly people suffer from dementia, the number of people with this disease is increasing rapidly. The causes of dementia are multiple, and the diagnosis of the different types of dementia is complicated since most patients display mixed dementias, and symptoms overlapping. Personalized diagnosis and treatments would be desirable, but this requires a deep knowledge of each type of dementia where a multidisciplinary approach would be ideal. Thus, the aim of this review is to summarize the features of the main types of dementia as well as to compilate the more recent findings on this subject, ranging from genetic and molecular studies to animal models, including the use of omics platforms based on powerful hybrid instrumental techniques, and neuroimage techniques. On the other hand, we consider the aspects that can prevent these disorders and depend on modifiable factors, such as diet, among others. Finally, new technologies, such as nanotechnology, can provide novel strategies for the administration of effective treatments. In this regard, our purpose is to provide the most updated and complete overview of the state of the art characteristics of these disorders.

Pharmacogenetics of the Glucagon-like Peptide-1 Receptor Agonist Liraglutide: A Step Towards Personalized Type 2 Diabetes Management

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) is a chronic metabolic disorder with increasing prevalence and a significant burden of long-term complications. Glucagon-like Peptide-1 receptor agonists (GLP-1 RAs) are a novel treatment option for T2DM, exerting optimal effects on glucose control and weight loss, and pleiotropic actions. Pharmacogenetics, a promising research field of precision medicine, investigates how gene variations can affect individual response to drug therapy, assuming that the diverse genetic architecture of patients with T2DM could be partly associated with the considerable inter-individual variability in the therapeutic response to GLP-1 RAs. This review aims to summarize current evidence related to T2DM risk variants, affecting the incretin pathway, focus on the pharmacogenetics of the GLP-1 RA liraglutide, and discuss their potential clinical implications in the management of this complex disorder.

METHODS

A literature search was performed using electronic biomedical databases, and the findings of key studies are summarized and discussed in this narrative review.

RESULTS

Available evidence suggests the involvement of genetic polymorphisms in GLP-1 Rgene in variation in glycemic response, metabolic parameters and gastric emptying in people treated with liraglutide. Polymorphisms in CNR1, CTRB1/2, TMEM114 and CHST3 loci were also shown to be implicated in the disturbance of the incretin homeostasis in T2DM. These findings warrant further investigation by future studies.

CONCLUSION

Robust findings from pharmacogenetic studies might be used to identify good responders to liraglutide treatment, in terms of both glycemic and weight control, thus reinforcing the patient-centered approach of T2DM management.

Relationship Between the Dynamics of Telomere Loss in Peripheral Blood Leukocytes From Knee Osteoarthritis Patients and Mitochondrial DNA Haplogroups

OBJECTIVE

To evaluate the evolution of telomere length from peripheral blood leukocytes (PBLs) in subjects from the Osteoarthritis Initiative (OAI) cohort in relation to the incidence of osteoarthritis (OA), and to explore its possible interactive influence with the mitochondrial DNA (mtDNA) haplogroup.

METHODS

Dynamics of telomere sequence loss were quantified in PBLs from initially healthy individuals (without symptoms or radiological signs), 78 carrying the mtDNA cluster HV, and 47 with cluster JT, from the OAI, during a 72-month follow-up period. The incidence of knee OA during this period (n = 39) was radiographically established when Kellgren-Lawrence (KL) score increased from < 2 at recruitment, to ≥ 2 at the end of 72 months of follow-up. Multivariate analysis using binary logistic regression was performed to assess PBL telomere loss and mtDNA haplogroups as associated risk factors of incidence of knee OA.

RESULTS

Carriers of cluster HV showed knee OA incidence twice that of the JT carriers (n = 30 vs 9). The rate of PBL telomere loss was higher in cluster HV carriers and in individuals with incident knee OA. Multivariate analysis showed that the dynamics of PBL telomere shortening can be a consistent risk marker of knee OA incidence. Subjects with nonincident knee OA showed a slower telomere loss than those with incident knee OA; the difference was more significant in carriers of cluster JT than in HV.

CONCLUSION

An increased rate of telomere loss in PBLs may reflect a systemic accelerated senescence phenotype that could be potentiated by the mitochondrial function, increasing the susceptibility of developing knee OA.

Adherence to oral glucose tolerance testing in children in stage 1 of type 1 diabetes: The TEDDY study

OBJECTIVE

To examine adherence to the oral glucose tolerance test (OGTT) in multiple islet autoantibody children in stage 1 of developing type 1 diabetes (T1D).

METHODS

Children are followed from birth in The Environmental Determinants of Diabetes in the Young (TEDDY) study. Completion of an OGTT is recommended every 6 months in children ≥3 years of age who are multiple islet autoantibody positive. Factors associated with adherence to the OGTT protocol were examined.

RESULTS

The average subject level adherence with the OGTT protocol was 62% although there were large differences across countries; Finnish participants and older children from Sweden were more adherent than participants from the United States and Germany. Factors associated with nonadherence included having a first-degree relative with T1D, using a local laboratory rather than a TEDDY center for the OGTT, and maternal underestimation of the child's risk for T1D. Children were more adherent to the OGTT if their mothers: were more satisfied with TEDDY participation, reported monitoring the child for T1D by checking blood glucose levels at home, and viewed participating in TEDDY as the primary way they were monitoring the child for T1D.

CONCLUSIONS

In a study of children in stage 1 of T1D, adherence to an OGTT protocol was suboptimal despite extensive efforts to communicate the child's high risk to parents. These findings provide important guidance for development of strategies to improve methods for detecting progression or the development of T1D in high-risk pediatric populations.

Metaanalysis Reveals Genetic Correlates of Osteoporosis Pathogenesis

OBJECTIVE

Osteoporosis is a growing healthcare burden. By identifying osteoporosis-promoting genetic variations, we can spotlight targets for new pharmacologic therapies that will improve patient outcomes. In this metaanalysis, we analyzed mesenchymal stem cell (MSC) biomarkers in patients with osteoporosis.

METHODS

We employed our Search Tag Analyze Resource for the Gene Expression Omnibus (STARGEO) platform to conduct a metaanalysis to define osteoporosis pathogenesis. We compared 15 osteoporotic and 14 healthy control MSC samples. We then analyzed the genetic signature in Ingenuity Pathway Analysis.

RESULTS

The top canonical pathways identified that were statistically significant included the serine peptidase inhibitor kazal type 1 pancreatic cancer pathway, calcium signaling, pancreatic adenocarcinoma signaling, axonal guidance signaling, and glutamate receptor signaling. Upstream regulators involved in this disease process included ESR1, dexamethasone, CTNNβ1, CREB1, and ERBB2.

CONCLUSION

Although there has been extensive research looking at the genetic basis for inflammatory arthritis, very little literature currently exists that has identified genetic pathways contributing to osteoporosis. Our study has identified several important genes involved in osteoporosis pathogenesis including ESR1, CTNNβ1, CREB1, and ERBB2. ESR1 has been shown to have numerous polymorphisms, which may play a prominent role in osteoporosis. The Wnt pathway, which includes the CTNNβ1 gene identified in our study, plays a prominent role in bone mass regulation. Wnt pathway polymorphisms can increase susceptibility to osteoporosis. Our analysis also suggests a potential mechanism for ERBB2 in osteoporosis through Semaphorin 4D (SEMA4D). Our metaanalysis identifies several genes and pathways that can be targeted to develop new anabolic drugs for osteoporosis treatment.

Evaluating Two Common Strategies for Research Participant Recruitment Into Autism Studies: Observational Study

BACKGROUND

Ongoing research is necessary to better understand the causes of autism spectrum disorder (ASD), the developmental outcomes for individuals diagnosed with ASD, and the efficacy of the interventions. However, it is often difficult to recruit sufficient numbers of participants for studies, and despite the prevalence of ASD (currently estimated to affect 1 in 54 children), little research has focused on how to efficiently recruit participants with ASD.

OBJECTIVE

The aim of this study was to determine the efficacy of two different paid advertisements-social media and radio advertising-in recruiting participants for a study enrolling people with ASD and their family members by examining the number of participants enrolled, the cost per participant, and the geographic reach of each type of advertising.

METHODS

We examined participant enrollment in a study following nonoverlapping paid advertisements on a popular FM radio station (aired in three cities across two states) and Facebook (six advertisements that ran in five cities across two states). The total paid investment in the radio campaign was $12,030 and that in the Facebook campaign was $2950. Following the advertising campaigns, 1391 participants in the study who were affiliated with the Houston, Texas, site received email invitations to participate in a brief survey about the ways in which they learned about the study (eg, social media, medical provider, website) and which of these were most influential in their decisions to participate; 374 (26.8%) of the participants completed this survey.

RESULTS

Social media advertising outperformed radio in all three parameters examined by enrolling more participants (338 vs 149), with a lower average cost per participant ($8.73 vs $80.74) and a wider geographic reach, based on a comparison of the number of zip codes within and outside of Texas for questionnaire respondents who rated social media as the most influential method of contact (n=367, χ21=5.85, P=.02). Of the 374 survey participants, 139 (37.2%) reported that they had seen the study on social media prior to enrollment, while only 9 (2.4%) said they heard about it via radio.

CONCLUSIONS

Our findings suggest that advertising on social media can efficiently reach a large pool of potential participants with ASD, increasing the likelihood of meeting study enrollment goals. Researchers should consider allocating at least some portion of recruitment dollars to social media platforms as a means of quickly and inexpensively reaching out to their target populations, including for studies with in-person procedures.

Family history identifies sporadic schizoaffective disorder as a subtype for genetic studies

Background

Schizophrenia is a heterogeneous disorder with strong genetic vulnerability. Family history of schizophrenia has been considered in genetic studies under several models. De novo genetic events seem to play a larger role in sporadic cases.

Aim

This study used the familial–sporadic distinction with the aim of identifying a more homogeneous phenotype to delineate the genetic and clinical complexity of schizophrenia.

Setting

The study was conducted at Weskoppies Hospital, Pretoria, South Africa.

Methods

The study included 384 participants with schizophrenia or schizoaffective disorder from the Afrikaner founder population in South Africa who are considered comparable to Caucasian patients from the United States. A comprehensive data capturing sheet was completed.

Results

When schizophrenia and schizoaffective disorder diagnoses were considered jointly, we found no significant differences between the sporadic and the familial groups for age at disease onset, season of birth, comorbid diagnoses, clinical symptomatology, history of suicide or marital status. When the diagnoses were examined separately, however, the sporadic schizoaffective disorder, bipolar type, was found to have a significantly lower age at onset (mean 20.6 vs. 25.3 years).

Conclusion

The sporadic schizoaffective disorder, bipolar type, forms a more homogeneous subgroup for genetic studies.

Crop Phenomics and High-Throughput Phenotyping: Past Decades, Current Challenges, and Future Perspectives

Since whole-genome sequencing of many crops has been achieved, crop functional genomics studies have stepped into the big-data and high-throughput era. However, acquisition of large-scale phenotypic data has become one of the major bottlenecks hindering crop breeding and functional genomics studies. Nevertheless, recent technological advances provide us potential solutions to relieve this bottleneck and to explore advanced methods for large-scale phenotyping data acquisition and processing in the coming years. In this article, we review the major progress on high-throughput phenotyping in controlled environments and field conditions as well as its use for post-harvest yield and quality assessment in the past decades. We then discuss the latest multi-omics research combining high-throughput phenotyping with genetic studies. Finally, we propose some conceptual challenges and provide our perspectives on how to bridge the phenotype-genotype gap. It is no doubt that accurate high-throughput phenotyping will accelerate plant genetic improvements and promote the next green revolution in crop breeding.

Factors associated with participation by African Americans in a study of the genetics of glaucoma

Objective: African Americans have been historically underrepresented in research studies. Our aim was to evaluate factors influencing enrollment in the Primary Open-Angle African American Glaucoma Genetics (POAAGG) study. Design: Patients approached to enroll in the POAAGG study were asked to complete a 15-item survey addressing demographic characteristics, knowledge of genetics and glaucoma, and opinions on human research. Survey responses were compared between subjects who enrolled (Enrollers) and did not enroll (Decliners) in the POAAGG study. Results: Enrollers (N = 190) were 3.7 years younger (P = 0.007) and had similar gender, education, and income level to Decliners (N = 117). Knowledge about genetics and glaucoma was similar between groups. Enrollers were more comfortable providing DNA for research studies (93.1% vs 54.1%; P < 0.001) and more likely to have participated in prior studies (P = 0.003) and consider participating in future studies (P < 0.001). Among Decliners, lack of time was the primary reason given for not enrolling. Conclusion: To increase participation of African Americans in genetic research studies, efforts should be made to raise comfort with DNA donation.

Vasculitis: Decade in Review

BACKGROUND

In the last decade, we have come to better understand and manage the vasculitides. The classification of vasculitides has been revised. Genome- wide association studies and linkage analyses have been undertaken in hope of better understanding the pathogenesis of vasculitides. Comprehensive genetic studies have highlighted new pathways that may guide us in more targeted therapies. Description of the monogenic forms of vasculitis, such as deficiency of adenosine deaminase type 2 (DADA2), Haploinsufficiency of A20 (HA20), have introduced a new perspective to vasculopathies, and introduced alternative treatments for these diseases.

CONCLUSION

In this review, the important discoveries in pathogenesis and consensus treatment recommendations from the past decade will be summarized.

What People Want to Know About Their Genes: A Critical Review of the Literature on Large-Scale Genome Sequencing Studies

From a public health perspective, the “All of Us” study provides an opportunity to isolate targeted and cost-effective prevention and early-detection strategies. Identifying motivations for participation in large-scale genomic sequencing (LSGS) studies, and motivations and preferences to receive results will help determine effective strategies for “All of Us” study implementation. This paper offers a critical review of the literature regarding LSGS for adult onset hereditary conditions where results could indicate an increased risk to develop disease. The purpose of this review is to synthesize studies which explored peoples’ motivations for participating in LSGS studies, and their desire to receive different types of genetic results. Participants were primarily motivated by altruism, desire to know more about their health, and curiosity. When asked about hypothetically receiving results, most participants in hypothetical studies wanted all results except those which were uncertain (i.e., a variant of uncertain significance (VUS)). However, participants in studies where results were returned preferred to receive only results for which an intervention was available, but also wanted VUS. Concerns about peoples’ understanding of results and possible psychosocial implications are noted. Most studies examined populations classified as “early adopters,” therefore, additional research on motivations and expectations among the general public, minority, and underserved populations is needed.

Development of 15 microsatellite markers in Acer triflorum (Aceraceae) and cross-amplification in congeneric species

PREMISE OF THE STUDY

Acer (Aceraceae) is an important genus in forest ecosystems in the Northern Hemisphere. In China, 151 species have been reported, and approximately 61 species are endemic. Thus, China is considered to host the greatest diversity of Acer, but markers are needed to evaluate the genetic structure and genetic diversity of these populations of wild Acer species.

METHODS AND RESULTS

Using an enriched genomic library, we developed and characterized 15 microsatellite primers for A. triflorum, 10 of which were polymorphic. The number of alleles varied from one to nine. The levels of observed heterozygosity and expected heterozygosity per locus ranged from 0.000 to 1.000 and 0.000 to 0.826, respectively. Most primers also successfully amplified in A. ginnala, A. griseum, A. mandshuricum, A. pseudosieboldianum, A. sinopurpurascens, A. tegmentosum, and A. ukurunduense.

CONCLUSIONS

These markers from A. triflorum will provide an opportunity to study genetic diversity and genetic structure in the genus Acer.

Macros in microRNA target identification: a comparative analysis of in silico, in vitro, and in vivo approaches to microRNA target identification

MicroRNAs (miRNAs) are short RNA molecules that modulate post-transcriptional gene expression by partial or incomplete base-pairing to the complementary sequences on their target genes. Sequence-based miRNA target gene recognition enables the utilization of computational methods, which are highly informative in identifying a subset of putative miRNA targets from the genome. Subsequently, single miRNA-target gene binding is evaluated experimentally by in vitro assays to validate and quantify the transcriptional or post-transcriptional effects of miRNA-target gene interaction. Although ex vivo approaches are instructive in providing a basis for further analyses, in vivo genetic studies are critical to determine the occurrence and biological relevance of miRNA targets under physiological conditions. In the present review, we summarize the important features of each of the experimental approaches, their technical and biological limitations, and future challenges in light of the complexity of miRNA target gene recognition.

Differences between blood donors and a population sample: implications for case-control studies

BACKGROUND

Selecting appropriate controls for studies of genetic variation in case series is important. The two major candidates involve the use of blood donors or a random sample of the population.

METHODS

We compare and contrast the two different populations of controls for studies of genetic variation using data from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). In addition we compute different biases using a series of hypothetical assumptions.

RESULTS

The study subjects who had been blood donors differed markedly from the general population in social, health-related, anthropometric, and personality-related variables. Using theoretical examples, we show that blood donors are a poor control group for non-genetic studies of diseases related to environmentally, behaviourally, or socially patterned exposures. However, we show that if blood donors are used as controls in genetic studies, these factors are unlikely to make a major difference in detecting true associations with relatively rare disorders (cumulative incidence through life of <10%). Nevertheless, for more common disorders, the reduction in accuracy resulting from the inclusion in any control population of individuals who have or will develop the disease in question can create a greater bias than can socially patterned factors.

CONCLUSIONS

Information about the medical history of a control and the parents of the control (as a proxy for whether the control will develop the disease) is more important with regard to the choice of controls than whether the controls are a random population sample or blood donors.

The physiological roles of phosducin: from retinal function to stress-dependent hypertension

In the time since its discovery, phosducin's functions have been intensively studied both in vivo and in vitro. Phosducin's most important biochemical feature in in vitro studies is its binding to heterotrimeric G protein βγ-subunits. Data on phosducin's in vivo relevance, however, have only recently been published but expand the range of biological actions, as shown both in animal models as well as in human studies. This review gives an overview of different aspects of phosducin biology ranging from structure, phylogeny of phosducin family members, posttranscriptional modification, biochemical features, localization and levels of expression to its physiological functions. Special emphasis will be placed on phosducin's function in the regulation of blood pressure. In the second part of this article, findings concerning cardiovascular regulation and their clinical relevance will be discussed on the basis of recently published data from gene-targeted mouse models and human genetic studies.

Accuracy of phenotyping of autistic children based on Internet implemented parent report

While strong familial evidence supports a substantial genetic contribution to the etiology of autism spectrum disorders (ASD), specific genetic abnormalities have been identified in only a small minority of all cases. In order to comprehensively delineate the genetic components of autism including the identification of rare and common variants, overall sample sizes an order of magnitude larger than those currently under study are critically needed. This will require rapid and scalable subject assessment paradigms that obviate clinic-based time-intensive behavioral phenotyping, which is a rate-limiting step. Here, we test the accuracy of a web-based approach to autism phenotyping implemented within the Interactive Autism Network (IAN). Families who were registered with the IAN and resided near one of the three study sites were eligible for the study. One hundred seven children ascertained from this pool who were verbal, age 4-17 years, and had Social Communication Questionnaire (SCQ) scores > or =12 (a profile that characterizes a majority of ASD-affected children in IAN) underwent a clinical confirmation battery. One hundred five of the 107 children were ASD positive (98%) by clinician's best estimate. One hundred four of these individuals (99%) were ASD positive by developmental history using the Autism Diagnostic Interview-Revised (ADI-R) and 97 (93%) were positive for ASD by developmental history and direct observational assessment (Autism Diagnostic Observational Schedule or expert clinician observation). These data support the reliability and feasibility of the IAN-implemented parent-report paradigms for the ascertainment of clinical ASD for large-scale genetic research.

Clear cell sarcoma: a case mimicking primary cutaneous malignant melanoma

Clear cell sarcoma (CCS) is a recently described variant of sarcoma characterized by prominent clear cells showing features similar to clear cell melanoma. This neoplasm was first described by Dr. Franz M. Erzinger. Primary CCS usually arises in deeper soft tissues, in association with fascia, tendons, or aponeuroses. Characteristic translocation t(12;22) (q13;q12) has been considered pathognomonic for CCS. Prognosis is related to tumor size. An early recognition and initial radical surgery is the key to a favourable outcome. We present a patient with an unusual neoplasm that resembled malignant melanoma.

An overview of Indian research in bipolar mood disorder

This review has been done after careful research of articles published in indian journal of psychiatry with the search words of manic depressive psychosis and bipolar mood disorder. Many articles in the following areas are included: 1) ETIOLOGY: genetic studies: 2) ETIOLOGY - neuro psychological impairment: 3) Adult bipolar disorder 4) Epidemological 5) Clinical picture - phenomenology: 6) Course of bipolar mood disorder: 7) Juvenile onset bipolar affective disorder 8) Secondary mania: 9) Clinical variables and mood disorders: 10) Disability: 11) Comorbidity: 12) TREATMENT: biological 13) Recent evidence: 14) Pharmacological evidence in special population. Though there seems to be significant contribution, there are still lot of areas which need careful intervention. The findings in various studies from the indian point of view are reviewed.

Familial transmission of derived phenotypes for molecular genetic studies of substance use disorders

Although family, twin, and adoption studies indicate that genes play a significant etiologic role in the development of substance use disorders (SUDs), detecting specific genes has been difficult due to uncertainties about how to define SUDs, genetic heterogeneity and variable phenotypic expression of SUD genotypes. We used data from families recruited into six contemporaneous studies of children and adults to derive candidate SUD phenotypes using principle factors factor analysis with varimax rotation. We previously found evidence of two SUD phenotypes in offspring: a psychopathology dimension and a cognitive impairment dimension. We found evidence for one SUD-related phenotype in adults that we term Psychopathology and Cognitive Impairment. Parental factor scores significantly predicted both offspring phenotypes, as well as parental SUD (OR=1.41, p<0.001) and offspring SUD (mother's phenotype: OR=1.34, p=0.04; father's phenotype: OR=1.33, p=0.01). Offspring phenotype predicted offspring SUD (psychopathology phenotype: OR=2.96, p<0.001; cognitive impairment: OR=1.33, p=0.04); in offspring, baseline psychopathology predicted SUD at follow-up assessments (OR=1.55, p=0.01). Results suggest that these candidate SUD phenotypes may be useful for genetic studies of SUD.

Interaction between birthweight and polymorphism in the calcium-sensing receptor gene in determination of adult bone mass: the Hertfordshire cohort study

OBJECTIVE

We sought evidence of interaction between single-nucleotide polymorphisms (SNP) in the calcium-sensing receptor (CASR) gene and early life in determination of bone mineral density (BMD) among individuals from the Hertfordshire Cohort Study.

METHODS

Four hundred ninety-eight men and 468 women aged 59-71 years were recruited. A lifestyle questionnaire was administered and BMD at lumbar spine and femoral neck was measured. DNA was obtained from whole blood samples using standard extraction techniques. Five SNP of the CASR gene termed CASRV1 (rs1801725, G-->T, S986A), CASRV2 (rs7614486, T-->G, untranslated), CASRV3 (rs4300957, untranslated), CASRV4 (rs3804592 G-->A, intron), and CASRV5 (rs1393189, T-->C, intron) were analyzed.

RESULTS

Among women the 11 genotype of the CASRV3 SNP was associated with higher lumbar spine BMD within the lowest birthweight tertile, while the opposite pattern was observed among individuals in the highest birthweight tertile (test for interaction on 1 df, p = 0.005, adjusted for age, body mass index, physical activity, dietary calcium intake, cigarette and alcohol consumption, social class, menopausal status, and hormone replacement therapy use). Similar relationships were seen at the total femur (p = 0.042, fully adjusted) with birthweight and at the total femur according to weight at 1 year tertile among women (p < 0.001, fully adjusted). One haplotype was associated with lumbar spine BMD in women (p = 0.008, fully adjusted); these findings were replicated in a second cohort.

CONCLUSION

We have found evidence of an interaction between a SNP of the CASR gene and birthweight in determination of bone mass in a UK female population.