[Concepts for the return of secondary genetic findings in medical diagnostics and research]. / Konzepte zur Mitteilung genetischer Zusatzbefunde in der medizinischen Diagnostik und Forschung.

High-throughput sequencing of whole genomes is technically already at a high level and is being discussed as a cost-effective alternative to other targeted, analytical procedures for clinical diagnosis of heritable disorders. On the other hand, with whole genome and whole exome sequencing, there is a high likelihood of uncovering secondary findings not associated with the primary aim of the investigation. This article tries to outline the current scientific and technical status of whole genome and whole exome sequencing and of the national and international recommendations concerning the handling of secondary genetic findings which are already available, above all in the research-related context and less so in the clinical context.

Health needs assessment for medical genetic services for congenital disorders in middle- and low-income nations.

Medical genetic services for the care and prevention of congenital disorders have received little attention in most middle- and low-income countries to date. In 2010, the World Health Organisation prioritized services for the care and prevention of birth defects in these nations, emphasising their importance in assisting such countries to reach their Millennium Development Goals. Health Needs Assessment is an inclusive, rational, epidemiological-assisted approach for providing information to plan, introduce and beneficially change health care services to improve the health of populations. It is intrinsic to much of the development of health care systems in industrialised nations. Its use by middle- and low-income countries to introduce and develop medical genetic services commensurate with their needs and circumstances would be beneficial. An approach to applying Health Needs Assessment in these circumstances is described.

International variation in physicians' attitudes towards prophylactic mastectomy - comparison between France, Germany, the Netherlands and the United Kingdom.

PURPOSE: Prophylactic mastectomy (PM) has proven to be the most effective method to reduce the risk of breast cancer in high-risk women. The present study aimed to present and compare the attitudes towards PM among physicians in France, Germany, the Netherlands and the United Kingdom (UK). PATIENTS AND METHODS: An international sample of 1196 general practitioners (GPs) and 927 breast surgeons (BS) were surveyed using a mailed questionnaire. RESULTS: Only 30% of the French and 27% of the German GPs were of opinion that PM should be an option for an unaffected female BRCA1/2 mutation carrier, as compared to 85% and 92% of the GPs in the Netherlands and UK, respectively. Similarly, 78% of the French and 66% of the German BS reported a positive attitude towards PM, as compared to 100% and 97% of the BS in the Netherlands and UK, respectively. In the whole sample of GPs, a positive attitude towards PM was associated with country of residence, being female, and having more knowledge of breast/ovarian cancer genetics, while among BS there was a positive association with country of residence and having more knowledge of breast/ovarian cancer genetics as well, and, in addition, with a higher number of newly diagnosed breast cancer patients last year. CONCLUSION: These results demonstrated the international variations in the attitude towards PM among physicians. This might reflect that different policies are adopted to prevent breast cancer in women at-risk.

Evaluation of Clinical Manifestations in Patients with Severe Lymphedema with and without CCBE1 Mutations.

The lymphedema-lymphangiectasia-intellectual disability (Hennekam) syndrome (HS) is characterised by a widespread congenital lymph vessel dysplasia manifesting as congenital lymphedema of the limbs and intestinal lymphangiectasia, accompanied by unusual facial morphology, variable intellectual disabilities and infrequently malformations. The syndrome is heterogeneous as mutations in the gene CCBE1 have been found responsible for the syndrome in only a subset of patients. We investigated whether it would be possible to predict the presence of a CCBE1 mutation based on phenotype by collecting clinical data of patients diagnosed with HS, with or without a CCBE1 mutation. We report here the results of 13 CCBE1 positive patients, 16 CCBE1 negative patients, who were clinically found to have classical HS, and 8 patients in whom the diagnosis was considered possible, but not certain, and in whom no CCBE1 mutation was identified. We found no statistically significant phenotypic differences between the 2 groups with the clinical HS phenotype, although the degree of lymphatic dysplasia tended to be more pronounced in the mutation positive group. We also screened 158 patients with less widespread and less pronounced forms of lymphatic dysplasia for CCBE1 mutations, and no mutation was detected in this group. Our results suggest that (1) CCBE1 mutations are present only in patients with a likely clinical diagnosis of HS, and not in patients with less marked forms of lymphatic dysplasia, and (2) that there are no major phenotypic differences between HS patients with or without CCBE1 mutations.

[Health insurance companies and medical genetics, what do they want to know? Expert opinions concerning medical genetic services]. / Was wollen Versicherungen wissen? Auskunftsersuchen privater Krankenversicherungen zu humangenetischen Leistungen.

Based on the compilation of medical opinions delivered by a medical genetic expert between 2002 and 2010, solicited by private health insurance companies in Germany, an analysis of the main issues raised was made to identify the information needs of company employees with respect to human and medical genetics. The findings are discussed and recommendations for improvement and further training are suggested.

A simple clinical model to estimate the probability of Marfan syndrome.

BACKGROUND: Marfan syndrome is a heritable connective tissue disease. Definitive diagnosis is complex, and requires sequencing of a large gene, FBN1. AIM: We aimed to develop a simple model to estimate the pre-test probability of Marfan syndrome. DESIGN: Prospective cross-sectional study. METHODS: We applied diagnostic standards for definitive diagnosis or exclusion of Marfan syndrome in 329 consecutive persons. In 208 persons with random assignment to our derivation group, we performed multivariate logistic regression to assess 14 clinical variables for inclusion in a prediction model with derivation of score points from the estimated coefficients. We created cut-offs to classify low, moderate and high probability of Marfan syndrome. For validation, we applied the model to the remaining 121 persons. RESULTS: We identified seven variables for inclusion in the final model, where we assigned four score points to ectopia lentis, two points to a family history of Marfan syndrome, and one point to previous thoracic aortic surgery, to pectus excavatum, to a wrist and thumb sign, to previous pneumothorax, and to skin striae. In the derivation group 12, 42 and 92% of persons with low (≤1 point), moderate (>1-3.5 points) or high pre-test probability (>3.5 points) had Marfan syndrome, compared to 12, 57 and 91%, respectively, in the validation group. Positive likelihood ratios were 13.96 and 8.54 in the high probability group of the derivation and validation group, respectively. CONCLUSION: A simple prediction model provides evidence for Marfan syndrome. This model can be used to identify patients who require definitive diagnostic work-up.

Analysis of phenotype and genotype information for the diagnosis of Marfan syndrome.

Marfan syndrome is considered a clinical diagnosis. Three diagnostic classifications comprising first, Marfan genotype with a causative FBN1 gene mutation; second, Marfan phenotype with clinical criteria of the original Ghent nosology (Ghent-1); and third, phenotype with clinical criteria of its current revision (Ghent-2) in 300 consecutive persons referred for confirmation or exclusion of Marfan syndrome (150 men, 150 women aged 35 ± 13 years) were used. Sequencing of TGBR1/2 genes was performed in 128 persons without FBN1 mutation. Marfan genotype was present in 140, Ghent-1 phenotype in 139, and Ghent-2 phenotype in 124 of 300 study patients. Marfan syndrome was confirmed in 94 and excluded in 129 persons consistently by all classifications, but classifications were discordant in 77 persons. With combined genotype and phenotype information confirmation of Marfan syndrome was finally achieved in 126 persons by Ghent-1 and in 125 persons by Ghent-2 among 140 persons with Marfan genotype, and exclusion was accomplished in 139 persons by Ghent-1 and in 141 persons by Ghent-2 among 160 persons without Marfan genotype. In total, genotype information changed final diagnoses in 22 persons with Ghent-1, and in 32 persons with Ghent-2. It is concluded that genotype information is essential for diagnosis or exclusion of Marfan syndrome.

Familial breast cancer: is it time to move from a reactive to a proactive role?

In 2004 the NICE guidelines on familial breast cancer advised Health Care Professionals that they should not actively seek to identify women with a family history of breast cancer. We have carried out a review of the evidence base and a large scale questionnaire survey of health professionals in four European countries. There is overwhelming support amongst GPs and surgeons against the premise that that health care professionals should not be proactive in identifying patients at risk of familial breast cancer. This that suggest the time is right to overturn the NICE decision.

Body weight gain induced by atypical antipsychotics: an extension of the monozygotic twin and sib pair study.

BACKGROUND AND OBJECTIVE: In our original study based on five monozygotic twin pairs and seven same-sex sib pairs, we previously showed that genetic factors contribute to body weight gain induced by the atypical antipsychotic clozapine. We aim to study this further by including patients treated with the atypical antipsychotics olanzapine or risperidone as well as opposite-sex sib pairs. METHODS: Twin and sib pairs were identified by a telephone screening. Measured data on weight and other clinical variables were obtained cross-sectionally and retrospectively from medical records. In seven monozygotic twin pairs and 12 sib pairs (total number of patients treated: n = 38, mean age 29.5 +/- 9.5, range 13.7-54.3 years), the similarity in BMI (kg/m(2)) change under these atypical antipsychotics (atypical Delta BMI) and upon additional inclusion of BMI change under prior antipsychotic medication (total Delta BMI) was explored. RESULTS: For total Delta BMI we found greater similarity in antipsychotic-induced BMI change in MZ twin pairs than in sib pairs (intrapair difference) with a heritability of h(2) = 0.6, but not for atypical Delta BMI, possibly because of a genetically influenced weight plateau achieved under antipsychotic medication. CONCLUSION: The results of the present and our previous report suggest a contribution of genetic factors in antipsychotic-induced weight gain of 60-80%.

Genetic screening in Europe.

Genetic screening has been defined as any kind of test performed systematically for the early detection or exclusion of a genetic disease, genetic predisposition or resistance to a disease, or to determine whether a person carries a gene variant that may produce disease in his or her offspring. In comparison to 'genetic testing', the term 'genetic screening' should be reserved for the explicit and systematic application of a diagnostic genetic test across a whole population of asymptomatic people (population screening) or a subset of a population such as pregnant women (prenatal/antenatal screening) or newborn infants (neonatal screening). This survey intends to present the current (2006-2008) status of genetic screening and the organization of genetic screening programmes in selected European countries as a background for future attempts to harmonize standards and procedures of genetic screening, an explicit aim of the European Network of Excellence, EuroGentest (www.eurogentest.org). Our report builds on the first comprehensive assessment of genetic screening programmes in Germany by the European Society of Human Genetics, starting with a workshop of experts in 1999, the production of background documentation in 2000, and a final report in 2003.

Prevalence of dural ectasia in 63 gene-mutation-positive patients with features of Marfan syndrome type 1 and Loeys-Dietz syndrome and report of 22 novel FBN1 mutations.

Marfan syndrome is an autosomal dominant disorder involving different organ systems. Marfan syndrome type 1 (MFS1) is caused by mutations in the FBN1 gene. Heterozygosity for mutations in the TGFBR1 or TGFBR2 genes cause Loeys-Dietz syndrome (LDS) types 2A and 2B that overlap with MFS1 in their clinical features. The phenotype of MFS1 is defined by the Ghent nosology, which classifies the clinical manifestations in major and minor criteria. Dural ectasia is one of the major criteria for Marfan syndrome but it is rarely tested for. We here report 22 novel and 9 recurrent mutations in the FBN1 gene in 36 patients with clinical features of Marfan syndrome. Sixty patients with identified mutations in the FBN1 gene and three patients with mutations in the TGFBR1 or TGFBR2 genes were examined for dural ectasia. Forty-seven of the 60 patients (78%) with MFS1 showed the dural ectasia criterion and 13 (22%) did not. Thirty-three (55%) patients were suspected of having Marfan syndrome and 24 (73%) of them had dural ectasia. Two of the three patients with LDS had dural ectasia.

Marfan syndrome: clinical consequences resulting from a medicolegal autopsy of a case of sudden death due to aortic rupture.

To investigate the sudden death of a 31-year-old man, a medicolegal autopsy was performed. Major findings were a dilated aortic root with a longitudinal rupture of the intima and dissection of aorta and right coronary artery and consequent tamponade of the pericardial sac. Moreover, arachnodactyly and other skeletal deformities in combination with the histological finding of a pseudocystic medionecrosis of the aortic wall were noted. By sequencing of the FBN1 gene, a mutation (1622G>A) leading to the diagnosis of Marfan syndrome was found. Genetic counseling was recommended to the relatives who reported that the father of the deceased had died at the same age from aortic rupture. While fortunately the child of the deceased lacked this mutation, it was found in his younger sister. The results of the autopsy thus enabled early diagnosis and beginning of treatment in the sister and thus a considerable statistical increase in lifespan. With this report, we want to show that medicolegal autopsies can also have medical consequences for relatives. We argue that in all sudden and unexpected deaths in young persons up to 35 years an autopsy should be performed, not only to detect unnatural causes of death but also to identify heritable diseases and thus aid the relatives.

Dyschromatosis universalis hereditaria: evidence for autosomal recessive inheritance and identification of a new locus on chromosome 12q21-q23.

Dyschromatosis universalis hereditaria (DUH) and dyschromatosis symmetrica hereditaria (DSH) are pigmentary dermatoses most commonly seen in Japan. Both disorders usually show autosomal dominant inheritance, although in some cases autosomal recessive inheritance was reported. DSH was mapped to chromosome 1q21.3, and mutations in the gene ADAR (DSRAD) were identified in Japanese, Chinese and Taiwanese families with autosomal dominant DSH. A second locus for dyschromatosis was mapped on chromosome 6q24.2-q25.2 in two Chinese families initially reported to be affected with DSH, but later suggested to have autosomal dominant DUH. The aim of this study was to investigate whether one of these two loci is involved in the development of DUH in a consanguineous Bedouin family from Saudi Arabia with four affected and three unaffected sibs, clearly pointing to autosomal recessive inheritance. After excluding mutations in ADAR and linkage to the candidate regions on chromosomes 1 and 6, we performed an single nucleotide polymorphism-based genome-wide scan for linkage with other loci. Under the assumption of autosomal recessive inheritance, we have identified a new locus for dyschromatosis on chromosome 12q21-q23 in this Arab family with a maximum logarithm of the odds (LOD) score of 3.4, spanning a distance of 18.9 cM. Our study revealed the first locus for autosomal recessive DUH and supports recent evidence that DSH and DUH are genetically distinct disorders.

Networking for rare diseases: a necessity for Europe.

Most rare diseases are life-threatening and chronically debilitating conditions, and the vast majority of them are genetically determined. Their individually low prevalence requires special combined efforts to address them so as to improve diagnosis, care and prevention. Though it is difficult to develop a public health policy specific to each rare disease, it is possible to have a global rather than a piecemeal approach in the areas of scientific and biomedical research, drug research and development, industry policy, information and training, social benefits, hospitalisation and outpatient care. In the recent past, several initiatives at EU and Member States levels have been taken and proved efficient in developing suitable solutions which are now having a positive impact on the quality of life of patients. These initiatives are presented here. They include the establishment of Orphanet, a database of rare diseases and orphan drugs providing an encyclopedia of rare diseases and a directory of associated expert services, the funding of research networks to boost the collaboration between research teams, as well as the funding of networks of clinical centres of reference to better serve the patients and contribute to developing clinical research.

The role of Frank elasticity in cholesteric elastomers.

The effect of Frank elasticity on deformations of cholesteric elastomers by mechanical stress applied perpendicular to the helix axis is studied by numerical minimization of the free energy. Above a critical strain, a solution with an only oscillating director is found to be stable in comparison to a distorted helix. At the critical strain, the contractions perpendicular to stress change discontinuously. The critical strain is found to increase with increasing Frank elasticity contribution to the free energy density, and to diverge when the conformation anisotropy of the polymer backbone vanishes. The results are compared with recent experiments which indicated that, in case of weak conformation anisotropies, the Frank elasticity contribution to the free energy cannot be neglected.

[Genetic diagnosis in medicine. An overview of basic concepts and applications]. / Genetische Diagnostik in der Medizin: Eine Ubersicht über die Grundlagen und Anwendungsbereiche.

Currently, more than half of all known monogenic diseases are characterized at the molecular (DNA) level. This opens the possibility to verify clinically suspected disease at the molecular level, to predict future (late-onset) disorders, to diagnose many diseases prenatally, and to screen the population for genetic traits. Genetic tests that can be performed in Germany, Austria and Switzerland are listed in a database maintained by the German Board of Human Genetics. As of May 2006, 678 different diseases were amenable to DNA-based testing, and 147 institutions offered such tests. The actual genetic test utilisation cannot be determined accurately, but can be deduced from the database of the "Zentralinstitut der Kassenärztlichen Bundesvereinigung". Data have been calculated for the years 1996- 2002. In this time interval, the number of individuals undergoing genetic testing doubled approximately every three years. The total number in 2002 can be estimated at 220,000.

Consequences of group fission for the patterns of relatedness among rhesus macaques.

When mammalian social groups exceed their optimal size, they often tend to split. In view of the potential evolutionary benefits, it should be more advantageous for animals to stay with kin, rather than nonkin, during such fission events. In the present study, the spontaneous fission of two social groups, R and S, of rhesus macaques living on Cayo Santiago, Puerto Rico, provided the opportunity to compare the kinship structure of the corresponding parent and daughter groups, using information on both maternal and paternal relatedness. In both instances, maternal half-siblings and pairs of animals from the same family were significantly more prevalent in the fission products than in the parent group. During the split of group R, significantly more paternal half-siblings stayed in the remnants of the parent group than joined the seceding group. Our findings are compatible with previous behavioural studies demonstrating that female primates bias their social behaviour more to maternal than to paternal kin, but that both types of half-siblings prefer each other more than unrelated animals. It remains to be clarified by future research, however, whether the observed co-segregation of paternal half-sibs in our study reflects active choice or is a by-product of the group-specific kin structures, prior to fission.