Tunneling through a localized barrier in a one-dimensional interacting electron gas has been studied recently using Luttinger liquid techniques. Stable phases with zero or unit transmission occur, as well as critical points with universal fractional transmission whose properties have only been calculated approximately, using a type of "ǫ-expansion". It may be possible to calculate the universal properties of these critical points exactly using the recent boundary conformal field theory technique, although difficulties arise from the ∞ number of conformal towers in this c = 4 theory and the absence of any apparent "fusion" principle. Here, we formulate the problem efficiently in this new language, and recover the critical properties of the stable phases.

The problem of an electron gas interacting via exchanging transverse gauge bosons is studied using the renormalization group method. The long wavelength behavior of the gauge field is shown to be in the Gaussian universality class with a dynamical exponent z = 3 in dimensions D ≥ 2. This implies that the gauge coupling constant is exactly marginal. Scattering of the electrons by the gauge mode leads to non-Fermi liquid behavior in D ≤ 3. The asymptotic electron and gauge Green's functions, interaction vertex, specific heat and resistivity are presented.

We reconsider the problem of deforming a conformal field theory to a neighboring theory which is again critical. An invariant formulation of this problem is important for understanding the underlying symmetry of string theory. We give a simple derivation of A. Sen's recent formula for the change in the stress tensor and show that, when correctly interpreted, it is coordinate-invariant. We give the corresponding superconformal perturbation for superfield backgrounds and explain why it has no direct analog for spin-field backgrounds. We reconsider the problem of deforming a conformal field theory to a neighboring theory which is again critical. An invariant formulation of this problem is important for understanding the underlying symmetry of string theory. We give a simple derivation of A. Sen's recent formula for the change in the stress tensor and show that, when correctly interpreted, it is coordinate-invariant. We give the corresponding superconformal perturbation for superfield backgrounds and explain why it has no direct analog for spin-field backgrounds. 10/90

Interpretation of sequence variants is an ongoing challenge and new approaches aim to increase stringency. The reclassification of variants has the potential to alter medical management and elicit psychosocial consequences for patients. The perspective of patients with an inherited cardiac disease and a clinically significant variant reclassification was explored through semi-structured phone interviews. Participants were recruited from two specialized multidisciplinary centers in Canada and Australia. Qualitative analysis was performed through a thematic analysis approach. Fifteen participants were interviewed, including 9 (60%) with an inherited cardiomyopathy and 6 (40%) with an inherited arrhythmia syndrome. Six (40%) patients had a classification upgrade, while 9 (60%) had a downgrade. Four major themes emerged: (1) reactions towards the reclassified variant; (2) impact on decision-making; (3) perception of the reclassification process; and (4) improvement of the reclassification process. Many patients adjusted to the reclassification, however some misunderstood the implications, impacting their responses and decision-making. In conclusion, careful discussion with patients about uncertainty and the potential for reclassification are crucial to ensure a deeper understanding of the outcome of genetic testing and impact on families.

Background: Rare sequence variation in genes underlying cardiac repolarization and common polygenic variation influence QT interval duration. However, current clinical genetic testing of individuals with unexplained QT prolongation is restricted to examination of monogenic rare variants. The recent emergence of large-scale biorepositories with sequence data enables examination of the joint contribution of rare and common variation to the QT interval in the population. Methods: We performed a genome wide association study (GWAS) of the QTc in 84,630 United Kingdom Biobank (UKB) participants and created a polygenic risk score (PRS). Among 26,976 participants with whole genome sequencing and electrocardiogram data in the Trans-Omics for Precision Medicine (TOPMed) program, we identified 160 carriers of putative pathogenic rare variants in 10 genes known to be associated with the QT interval. We examined QTc associations with the PRS and with rare variants in TOPMed. Results: Fifty-four independent loci were identified by GWAS in the UKB. Twenty-one loci were novel, of which 12 were replicated in TOPMed. The PRS comprising 1,110,494 common variants was significantly associated with the QTc in TOPMed (ΔQTc/ decile of PRS = 1.4 ms, 95% CI 1.3 -1.5; p-value=1.1×10 -196 ). Carriers of putative pathogenic rare variants had longer QTc than non-carriers (ΔQTc=10.9 ms [7.4-14.4]). 23.7% of individuals with QTc>480 ms carried either a monogenic rare variant or had a PRS in the top decile (3.4% monogenic, 21% top decile of PRS). Conclusions: QTc duration in the population is influenced by both rare variants in genes underlying cardiac repolarization and polygenic risk, with a sizeable contribution from polygenic risk. Comprehensive assessment of the genetic determinants of QTc prolongation includes incorporation of both polygenic and monogenic risk.

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Inherited arrhythmia conditions (IAC) can lead to sudden cardiac death at any age, and relatives of an affected person have up to a 50% chance of inheriting the condition and are at risk for developing features. Cascade testing is a stepwise approach for identifying relatives at risk for IACs through clinical screening and genetic testing. Early detection can reduce morbidity and mortality for affected individuals and determine potential risk mitigation strategies for relatives. However, cardiovascular genetic studies have reported an incomplete uptake of cascade testing in at-risk relatives. We explored patient perspectives on cascade testing for IACs and alternative approaches to family communication. Twelve semi-structured phone interviews were conducted with probands of the British Columbia Inherited Arrhythmia Program confirmed to carry a pathogenic or likely pathogenic variant in a gene associated with an IAC. Thematic analysis of transcripts through an iterative coding process revealed five main themes: (a) a stepwise approach is followed in disclosing risk to relatives, (b) relatives' autonomy in cascade testing is supported, (c) lived experience with the condition influences disclosure and uptake of cascade testing, (d) collaborative approach to informing relatives reduces negative impact of disclosure, and (e) direct contact from a healthcare provider is viewed as acceptable. The findings highlight this patient cohort's experiences and opinions with approaches to disclosure and demonstrate their understanding and acceptance of their relatives' approaches to cascade testing.In addition, while the notion of direct contact was generally accepted, a collaborative approach to contacting relatives between the proband and provider may be most effective.