Variant characterisation and clinical profile in a large cohort of patients with Ellis-van Creveld syndrome and a family with Weyers acrofacial dysostosis.

BACKGROUND: Ellis-van Creveld syndrome (EvC) is a recessive disorder characterised by acromesomelic limb shortening, postaxial polydactyly, nail-teeth dysplasia and congenital cardiac defects, primarily caused by pathogenic variants in EVC or EVC2. Weyers acrofacial dysostosis (WAD) is an ultra-rare dominant condition allelic to EvC. The present work aimed to enhance current knowledge on the clinical manifestations of EvC and WAD and broaden their mutational spectrum. METHODS: We conducted molecular studies in 46 individuals from 43 unrelated families with a preliminary clinical diagnosis of EvC and 3 affected individuals from a family with WAD and retrospectively analysed clinical data. The deleterious effect of selected variants of uncertain significance was evaluated by cellular assays. MAIN RESULTS: We identified pathogenic variants in EVC/EVC2 in affected individuals from 41 of the 43 families with EvC. Patients from each of the two remaining families were found with a homozygous splicing variant in WDR35 and a de novo heterozygous frameshift variant in GLI3, respectively. The phenotype of these patients showed a remarkable overlap with EvC. A novel EVC2 C-terminal truncating variant was identified in the family with WAD. Deep phenotyping of the cohort recapitulated 'classical EvC findings' in the literature and highlighted findings previously undescribed or rarely described as part of EvC. CONCLUSIONS: This study presents the largest cohort of living patients with EvC to date, contributing to better understanding of the full clinical spectrum of EvC. We also provide comprehensive information on the EVC/EVC2 mutational landscape and add GLI3 to the list of genes associated with EvC-like phenotypes.

Aortic dissection in a young male with persistent ductus arteriosus and a novel variant in MYLK.

Pathogenic variants in several genes involved in the function or regulation of smooth muscle cells (SMC) are known to predispose to congenital heart disease and thoracic aortic aneurysm and dissection (TAAD). Variants in MYLK are primarily known to predispose to TAAD, but a growing body of evidence points toward MYLK also playing an essential role in the regulation of SMC contraction outside the aorta. In this case report, we present a patient with co-occurrence of persistent ductus arteriosus (PDA) and thoracic aortic dissection. Genetic analyses revealed a novel splice acceptor variant (c.3986-1G > A) in MYLK, which segregated with disease in the family. RNA-analyses on fibroblasts showed that the variant induced skipping of exon 24, which resulted in an in-frame deletion of 101 amino acids. These findings suggest that MYLK-associated disease could include a broader phenotypic spectrum than isolated TAAD, including PDA and obstructive pulmonary disease. Genetic analyses could be considered in families with TAAD and PDA or obstructive pulmonary disease.

Carriers of COL3A1 pathogenic variants in Denmark: Interfamilial variability in severity and outcome of elective surgical procedures.

The study describes all patients in Denmark with vascular Ehlers-Danlos syndrome (vEDS). Carriers of pathogenic or likely pathogenic COL3A1 variants were retrospectively identified through registries and specialized clinics. Medical records were reviewed for vascular- or organ ruptures and invasive procedures performed. Identified families were divided by variant type (null, splice, and missense) and familial phenotypes (severe or attenuated). Families in which at least one carrier has suffered a major event before the age of 30 were classified as severe, whereas families in which at least three carriers had reached the age of 40 without a major event were classified as attenuated. Eighty-seven persons (59 still alive) from 25 families were included with a mean observation time of 44 years. Sixty-seven percent of patients could be subclassified in a familial phenotype. Thirty-one major events were observed. Eleven complications in 172 invasive procedures were recorded. No fatal complications to elective surgery were observed. The type of COL3A1 variant did not reliably predict phenotype, but a pattern of intrafamilial consistency emerged with some families showing an attenuated form of vEDS. Elective medical procedures appear to be safer than previously thought, although data only allow for conclusions regarding individuals from families with the attenuated form of vEDS.

Novel LOX Variants in Five Families with Aortic/Arterial Aneurysm and Dissection with Variable Connective Tissue Findings.

Thoracic aortic aneurysm and dissection (TAAD) is a major cause of cardiovascular morbidity and mortality. Loss-of-function variants in LOX, encoding the extracellular matrix crosslinking enzyme lysyl oxidase, have been reported to cause familial TAAD. Using a next-generation TAAD gene panel, we identified five additional probands carrying LOX variants, including two missense variants affecting highly conserved amino acids in the LOX catalytic domain and three truncating variants. Connective tissue manifestations are apparent in a substantial fraction of the variant carriers. Some LOX variant carriers presented with TAAD early in life, while others had normal aortic diameters at an advanced age. Finally, we identified the first patient with spontaneous coronary artery dissection carrying a LOX variant. In conclusion, our data demonstrate that loss-of-function LOX variants cause a spectrum of aortic and arterial aneurysmal disease, often combined with connective tissue findings.

Severe congenital cutis laxa: Identification of novel homozygous LOX gene variants in two families.

We report three babies from two families with a severe lethal form of congenital cutis laxa. All three had redundant and doughy-textured skin and two siblings from one family had facial dysmorphism. Echocardiograms showed thickened and poorly contractile hearts, arterial dilatation and tortuosity. Post-mortem examination in two of the babies further revealed widespread ectasia and tortuosity of medium and large sized arteries, myocardial hypertrophy, rib and skull fractures. The presence of fractures initially suggested a diagnosis of osteogenesis imperfecta. Under light microscopy bony matrices were abnormal and arterial wall architecture was grossly abnormal showing fragmented elastic fibres. Molecular analysis of known cutis laxa genes did not yield any pathogenic defects. Whole exome sequencing of DNA following informed consent identified two separate homozygous variants in the LOX (Lysyl Oxidase) gene. LOX belongs to the 5-lysyl oxidase gene family involved in initiation of cross-linking of elastin and collagen. A mouse model of a different variant in this gene recapitulates the phenotype seen in the three babies. Our findings suggest that the LOX gene is a novel cause of severe congenital cutis laxa with arterial tortuosity, bone fragility and respiratory failure.

[Genetic screening of adopted individuals].

Information regarding hereditary disease predisposition is generally inaccessible for adoptees. The lack of family history restricts access to various surveillance programmes and the overall health of the adoptee. Genetic screening of asymptomatic adoptees could be a compensational tool. However, variant classification is difficult, even more so in certain ethnic groups and in cases where there is no knowledge of family history, as summarised in this review. The usefulness of genetic screening of asymptomatic adoptees is still unknown and requires further research for clarification.

[Genetic screening of prospective parents].

Risk of genetic diseases with autosomal recessive or X-linked inheritance can be unknown to prospective parents until an affected child is born. New technology has enabled carrier screening for hundreds of genetic diseases (expanded carrier screening, ECS). I Denmark, each year estimated 100-180 children are born affected with a serious condition which could have been detected with ECS of the parents. This review describes the considerations and perspectives of a systematic genetic screening programme for prospective parents in the Danish healthcare system.

Direct to consumer genetic testing in Denmark-public knowledge, use, and attitudes.

Direct to consumer genetic testing (DTC-GT) is offered by commercial companies, but the use in the general population has only been sparsely investigated. A questionnaire was sent to 2013 representative Danish citizens asking about their awareness and use of DTC-GT. Individuals who had undergone a genetic test were interviewed to determine if the results had been understood correctly. A pilot study with 2469 questionnaires was performed before this study. In total, 45.4% of the individuals (n = 913/2013) had knowledge about DTC-GT and 2.5% (n = (18 + 5)/913) previously had a genetic test by a private company and 5.8% through the public health care system (n = (48 + 5)/913). Curiosity about own genetic information was the most frequent motivation (40.9%, n = 9/22) as well as knowledge of ancestry (36.4%, n = 8/22) and advice about lifestyle, exercise, or diet (36.4%, n = 8/22). Test of own disease risk was given as a reason in 27.3% (n = 6/22) and seeking possible explanation of specific symptoms in 13.6% (n = 3/22). 50% (n = 11/22) answered that they had become concerned after the test, and 17.4% (n = 4/23) had consulted their GP. Interviews in a subset of respondents from the pilot study revealed problems with understanding the results. One problem was how to interpret the genetic test results with respect to individual risk for a disease. For example, the difference between disease causing genetic variants in monogenetic diseases versus statistical risks by SNPs in multifactorial diseases was not understood by the respondents.

[The Danish screening programme for haemoglobinopathies].

The prevalence of people in Denmark descending from areas with a high prevalence of haemoglobinopathies is approximately one tenth and increasing. Since 1995, the Danish Health Authority has recommended haemoglobinopathy screening of pregnant women with ethnic roots outside Northern Europe. Partners of pregnant haemoglobinopathy carriers are also tested. Carrier state in both parents leads to genetic counselling, and prenatal diagnostics of the foetus (chorionic villus biopsy or amniocentesis) is offered, which can lead to abortion and/or preimplantation genetic screening for future pregnancies, as discussed in this review.

Expanding the cerebrovascular phenotype of the p.R258H variant in ACTA2 related hereditary thoracic aortic disease (HTAD).

Heterozygous variants in smooth muscle alpha-actin gene (ACTA2) are the most frequent cause of autosomal dominant hereditary thoracic aortic disease (HTAD). Several genotype-phenotype associations have been described, including a severe multisystemic smooth muscle disorder associated with de novo ACTA2 p.R179 variants, characterized by highly penetrant and early onset vascular disease, involvement of smooth muscle cell (SMC)-dependent organs and a distinct cerebrovascular phenotype. Missense variants at position 258 (p.R258C and p.R258H) have also been reported to have a more severe presentation including an increased risk for aortic dissection and a high risk of stroke. It has previously been suggested that the cerebrovascular phenotype of patients with p.R258 variants could represent a mild presentation of the cerebrovascular phenotype associated with p.R179 variants. Here we report on a five generation HTAD family with the p.R258H variant and describe the cerebrovascular findings seen in three family members, to expand on the previously reported phenotype associated with variants at this codon.

Phenotypic presentations of Hajdu-Cheney syndrome according to age - 5 distinct clinical presentations.

We present five Danish individuals with Hajdu-Cheney syndrome (HJCYS) (OMIM #102500), a rare multisystem skeletal disorder with distinctive facies, generalised osteoporosis and progressive focal bone destruction. In four cases positive genetic screening of exon 34 of NOTCH2 supported the clinical diagnosis; in one of these cases, mosaicism was demonstrated, which, to our knowledge, has not previously been reported. In one case no genetic testing was performed since the phenotype was definite, and the diagnosis in the mother was genetically confirmed. The age of the patients differs widely from ten to 57 years, allowing a natural history description of the phenotype associated with this ultra-rare condition. The evolution of the condition is most apparent in the incremental bone loss leading to osteoporosis and the acro-osteolysis, both of which contribute significantly to disease burden.

Translation and Adaptation of the Genetic Counselling Outcome Scale (GCOS-24) for Use in Denmark.

Outcome measurement in clinical genetics is challenging. Robust outcome measures are needed to provide evidence to support service development within genetic counseling. The Genetic Counselling Outcome Scale (GCOS-24), a Patient Reported Outcome Measure (PROM), was developed in English and validated with clinical genetics patients in the British NHS. This study reports the translation and adaptation of the GCOS-24 for use in Denmark. GCOS-24 was translated and back translated, supervised by an expert committee. Feedback on the first version was collected from genetic counseling patients in qualitative interviews focusing on instructions for use, response options and specific items considered semantically difficult. After further adjustment the adapted and translated version was administered to a second sample of patients, with responses analyzed using descriptive statistics. Eighteen interviews were conducted, and led to adjustment of item wording. Sixty-one patients completed the final version GCOS-24dk. Internal consistency is good (Cronbach's α =0.79), with an acceptable number of missing responses and no floor or ceiling effect observed. GCOS-24 has been successfully translated and adapted for use in a Danish setting. The study confirms the feasibility of local adaptation of patient reported outcome measures and stresses the importance of adaptation, even across quite similar populations and health care systems.

[Presymptomatic genetic testing in minors should only be performed when intervention is possible]. / Præsymptomatisk genetisk testning af børn bør kun foretages ved mulighed for intervention.

Presymptomatic genetic testing in minors is subject to debate. We reviewed guidelines on the subject from four large medical genetics societies. A general consensus exists regarding presymptomatic testing with the main justification for such testing being the direct benefit to the child through medical intervention or preventive measures. The child's best interest is central, but there is disagreement as to whether psychosocial and familial aspects should be included in this concept. Empirical evidence is lacking. We recommend increased awareness regarding the complexity of this issue.

[The genome and cardiology].

Several cardiac diseases are autosomal dominantly inherited. This includes cardiomyopathies, primary arrhythmias (channelopathies), dyslipidaemias, premature ischaemic heart diseases and diseases of the thoracic aorta. Sudden cardiac death in the young is also often due to one of the inherited cardiac diseases. Clinical and genetic cascade family screening of the relatives to patients with inherited cardiac diseases is now organized in a national network of centres of cardiology, sharing pedigrees, clinical and genetic information. This gives unique opportunities for offering focused prophylaxis in the group of high-risk relatives.

[Thorough family history and a multidisciplinary approach are important in sudden cardiac deaths]. / Grundig familieanamnese og et multidisciplinært samarbejde er vigtigt ved udredning af årsager til pludselig hjertedød.

Sudden cardiac death (SCD) is rare, yet well-known in children and adolescents. We present two cases of aborted SCD which reminds us of the importance of comprehensive family history as it proved difficult to ask the right questions revealing the number of family members with cardiac symptoms. Earlier recognition of sudden deaths in the family might have led to more extensive multidisciplinary examinations, and earlier diagnosis.

[Potential problems in obtaining insurance concern patients referred for genetic counseling].

In Denmark insurance companies may request information regarding current and past disease of the applicants and their family when insurance is requested but they are prohibited from requesting information regarding the applicants' genetically determined risk of future disease. We report a web-based survey in which 46 health-care providers reported how often they met concerns regarding insurance. Concerns were expressed in 1:17 contacts and led to discontinuation of the work-up in 1:200. The providers had knowledge of 86 actual cases with reports of genetic discrimination regarding insurance.

Early diphtheria-tetanus-pertussis vaccination associated with higher female mortality and no difference in male mortality in a cohort of low birthweight children: an observational study within a randomised trial.

BACKGROUND: Studies from low-income countries have suggested that diphtheria-tetanus-pertussis (DTP) vaccine provided after Bacille Calmette-Guerin (BCG) vaccination may have a negative effect on female survival. The authors examined the effect of DTP in a cohort of low birthweight (LBW) infants. METHODS: 2320 LBW newborns were visited at 2, 6 and 12 months of age to assess nutritional and vaccination status. The authors examined survival until the 6-month visit for children who were DTP vaccinated and DTP unvaccinated at the 2-month visit. RESULTS: Two-thirds of the children had received DTP at 2 months and 50 deaths occurred between the 2-month and 6-month visits. DTP vaccinated children had a better anthropometric status for all indices than DTP unvaccinated children. Small mid-upper arm circumference (MUAC) was the strongest predictor of mortality. The death rate ratio (DRR) for DTP vaccinated versus DTP unvaccinated children differed significantly for girls (DRR 2.45; 95% CI 0.93 to 6.45) and boys (DRR 0.53; 95% CI 0.23 to 1.20) (p=0.018, homogeneity test). Adjusting for MUAC, the overall effect for DTP vaccinated children was 2.62 (95% CI 1.34 to 5.09); DRR was 5.68 (95% CI 1.83 to 17.7) for girls and 1.29 (95% CI 0.56 to 2.97) for boys (p=0.023, homogeneity test). While anthropometric indices were a strong predictor of mortality among boys, there was little or no association for girls. CONCLUSION: Surprisingly, even though the children with the best nutritional status were vaccinated early, early DTP vaccination was associated with increased mortality for girls.

Attitudes towards abortion among trainees in obstetrics/gynecology and clinical genetics.

This study aimed to provide knowledge about attitudes towards abortion among Danish physicians in training in the specialties of obstetrics/gynecology and clinical genetics. The study was a questionnaire survey among trainees in these specialties. Ninety-six responded. Trainees in clinical genetics were more pro-abortion than those in obstetrics/gynecology (p=0.04). Of the respondents, 30 versus 48% found working with early and late abortions unpleasant. Nearly half agreed that they had chosen their specialty despite having to counsel and treat women having abortions. Twenty-one percent agreed that working with late abortion affected their job satisfaction negatively. Those agreeing with the above statements had a tendency towards lower pro-abortion scores than those who were indifferent or who disagreed but the differences were not significant. A substantial fraction of physicians in training have negative feelings associated with abortion-related work and require support in handling and coping with these challenges.

The Effect of 50 000 IU Vitamin A with BCG Vaccine at Birth on Growth in the First Year of Life.

Vitamin A supplements may interact with diphtheria-tetanus-pertussis (DTP) vaccine causing increased female mortality. In a randomised trial of neonatal vitamin A supplementation (VAS), we examined growth during the first year of life in 808 children, pursuing the hypothesis that a negative interaction between VAS and DTP in girls would be reflected in growth. Length and weight were measured at 6 weekly visits and WHO-growth-reference z-scores derived. Neonatal VAS had no effect on anthropometric measures at 12 months, but may interact sex differentially with routine vaccines. While BCG was the most recent vaccine, neonatal VAS benefitted growth (difference in weight-for-length z-score (dWFL: 0.31(95% CI: 0.03-0.59)). While DTP was the most recent vaccine, VAS tended to affect growth adversely in girls (dWFL = -0.21 (-0.48-0.06)). After measles vaccine (MV) there was no overall effect of neonatal VAS. The VAS effect differed significantly between the BCG and DTP windows (P = 0.03), and the difference was borderline significant between the DTP and MV windows for girls (P = 0.09).