Filling the gap: Genetic risk assessment in hypercholesterolemia using LDL-C and LPA genetic scores

Routine genetic testing in hypercholesterolemia patients reveals a causative monogenic variant in less than 50% of affected individuals. Incomplete genetic characterization is partly due to polygenic factors influencing low-density-lipoprotein-cholesterol (LDL-C). Additionally, functional variants in the LPA gene affect lipoprotein(a)-associated cholesterol concentrations but are difficult to determine due to the complex structure of the LPA gene. In this study we examined whether complementing standard sequencing with the analysis of genetic scores associated with LDL-C and Lp(a) concentrations improves the diagnostic output in hypercholesterolemia patients. 1.020 individuals including 252 clinically diagnosed hypercholesterolemia patients from the FH Register Austria were analyzed by massive-parallel-sequencing of candidate genes combined with array genotyping, identifying nine novel variants in LDLR. For each individual, validated genetic scores associated with elevated LDL-C and Lp(a) were calculated based on imputed genotypes. Integrating these scores especially the score for Lp(a) increased the proportion of individuals with a clearly defined disease etiology to 68.8% compared to 46.6% in standard genetic testing. The study highlights the major role of Lp(a) in disease etiology in clinically diagnosed hypercholesterolemia patients, of which parts are misclassified. Screening for monogenic causes of hypercholesterolemia and genetic scores for LDL-C and Lp(a) permits more precise diagnosis, allowing individualized treatment.

Array genotyping as diagnostic approach in medical genetics

Genotyping arrays are by far the most widely used genetic tests but are not generally utilized for diagnostic purposes in a medical context. In the present study, we examined the diagnostic value of a standard genotyping array (Illumina Global Screening Array) for a range of indications. Applications included stand‐alone testing for specific variants (32 variants in 10 genes), first‐tier array variant screening for monogenic conditions (10 different autosomal recessive metabolic diseases), and diagnostic workup for specific conditions caused by variants in multiple genes (suspected familial breast and ovarian cancer, and hypercholesterolemia). Our analyses showed a high analytical sensitivity and specificity of array‐based analyses for validated and non‐validated variants, and identified pitfalls that require attention. Ethical‐legal assessment highlighted the need for a software solution that allows for individual indication‐based consent and the reliable exclusion of non‐consented results. Cost/time assessment revealed excellent performance of diagnostic array analyses, depending on indication, proband data, and array design. We have implemented some analyses in our diagnostic portfolio, but array optimization is required for the implementation of other indications.

The genetic counseling profession in Austria: Stakeholders' perspectives

In contrast to most European countries, genetic counseling in Austria, Germany, and German-speaking Switzerland is exclusively carried out by medical doctors. In this study, we investigate the perspectives of key clinician stakeholders in Austrian genetics services regarding prerequisites, opportunities, and challenges of implementing master's trained genetic counselors. Semi-structured interviews with open-ended questions and thematic analysis were carried out with nine participants, mostly medical geneticists at different hierarchy levels from three Centers for Medical Genetics in Austria. Several Austrian medical geneticists strongly object to the implementation of non-physician genetic counselors, and representatives of 3/6 medical genetic centers declined to be interviewed. Semantic framing was identified as a critical factor: In German medical language, patient consultations carried out by medical geneticists are generally called 'Genetische Beratung' (genetic counseling), and many medical geneticists see themselves primarily as 'Genetische Berater' (genetic counselors). 'Genetic counseling' is specified as an exclusively medical task in Austrian law. There is apprehension that the introduction of non-physician genetic counselors could reduce quality and undermine the position of medical genetics as a clinical specialty. The situation in Austria resembles that in Germany. Our study highlights the need for a clear definition of roles, expertise, and scope of practice of different genetic professionals. The integration of genetic counselors into Austrian genetics services is most likely acceptable in multi-professional teams, closely affiliated with medical genetic services, and under the medico-legal oversight of medical geneticists.

Prospects and challenges for the genetic counsellor profession in the German-speaking countries: report of a workshop

The genetic counsellor profession has not yet been established in the German-speaking countries. In 2019 the Medical University of Innsbruck inaugurated the first German-taught Master’s degree programme in Genetic and Genomic Counselling. In order to discuss prospects and challenges of the genetic counsellor profession in Germany, Austria and Switzerland (DACH region), the MSc programme team organized a two-day workshop with international speakers and medical geneticists from the DACH region. Day 1 was dedicated to the history, training and international profile of the genetic counsellor profession. Day 2 focused on four specific topics: (i) professional role, (ii) acceptance and job title, (iii) formal requirements and (iv) remuneration concepts for genetic counsellors in the DACH region. The workshop showed that the key factor for the successful implementation of the genetic counsellor profession is acceptance and trust within the medical genetics team. Genetic counsellors complement patient care in aspects that might be underserved considering the increasing demand of counselling in genomic medicine. Successful establishment of the genetic counsellor profession will entail the development of interprofessional teams under medical supervision and in the team of medical geneticists.

Mesenchyme Forkhead 1 (FOXC2) plays a key role in metastasis and is associated with aggressive basal-like breast cancers

The metastatic spread of epithelial cancer cells from the primary tumor to distant organs mimics the cell migrations that occur during embryogenesis. Using gene expression profiling, we have found that the FOXC2 transcription factor, which is involved in specifying mesenchymal cell fate during embryogenesis, is associated with the metastatic capabilities of cancer cells. FOXC2 expression is required for the ability of murine mammary carcinoma cells to metastasize to the lung, and overexpression of FOXC2 enhances the metastatic ability of mouse mammary carcinoma cells. We show that FOXC2 expression is induced in cells undergoing epithelial-mesenchymal transitions (EMTs) triggered by a number of signals, including TGF-beta1 and several EMT-inducing transcription factors, such as Snail, Twist, and Goosecoid. FOXC2 specifically promotes mesenchymal differentiation during an EMT and may serve as a key mediator to orchestrate the mesenchymal component of the EMT program. Expression of FOXC2 is significantly correlated with the highly aggressive basal-like subtype of human breast cancers. These observations indicate that FOXC2 plays a central role in promoting invasion and metastasis and that it may prove to be a highly specific molecular marker for human basal-like breast cancers.