👤 Margaret R Spitz

Familial hypercholesterolemia (FH) is a genetic disorder leading to elevated low-density lipoprotein cholesterol (LDL-c) and increased risk for early atherosclerotic cardiovascular disease (ASCVD). While the 3 primary genes (LDLR, APOB, and PCSK9) associated with monogenic FH have been well established, rare variants remain challenging to interpret. We report a novel APOB variant, c.9498G>C (p.Lys3166Asn) in the region of the apolipoprotein B100 that is involved in the binding to the LDL receptor (LDLR). This variant was identified in multiple unrelated families with FH. We initially observed this variant in the proband with severe hypercholesterolemia and early ASCVD. Familial testing showed complete segregation of the variant with FH in the proband's family in all tested individuals with hypercholesterolemia. Further collaboration with diagnostic laboratories revealed 3 additional probands with the same variant and severe hypercholesterolemia. These findings suggest that this variant causes FH; however, functional studies are needed for definitive confirmation. This case underscores the importance of collaborative data sharing in variant interpretation and the role of case reports in enhancing genetic diagnosis for FH. Show less

In anticipation of updates to cholesterol guidelines globally, evidence since the most recent iteration of recommendations across US and Europe for risk assessment and lipid management are reviewed. ASCVD risk estimation is at the core of determining lipid lowering goals and consideration for therapies. In primary prevention, incorporation of the PREVENT equations will be featured in updated guidelines, which will likely demarcate new, lower risk thresholds compared to the prior Pooled Cohort Equations. Additionally, the use of coronary artery calcium (CAC) improves risk estimation to inform medication allocation and LDL-C goals beyond traditional risk factor risk estimation. To achieve lower LDL-C, many adults will need multiple lipid-lowering medications. For high-risk individuals, combination therapy with low/moderate intensity statin and ezetimibe or bempedoic acid should be considered. Additionally, proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i) therapies can be used to attain lower LDL-C in high-risk individuals, including those with clinical ASCVD or a high CAC burden. In very-high risk patients, treatment to LDL-C values as low as <30 mg/dL further reduces ASCVD risk without significant adverse events. Among individuals treated with PSCK9i therapy, those with elevated Lp(a) may have greater ASCVD risk reduction and may be a patient population that is prioritized for PCSK9i until therapies directly targeting Lp(a) are available. An ASCVD risk-based approach should be the foundation for determining LDL-C goals with consideration that multiple lipid-lowering therapies are often necessary for high and very-high risk patients who were treated to very low LDL-C in more recent randomized controlled trials. Show less

The role of leptin in regulating cardiac function is still controversial with conflicting results in clinical and preclinical studies. However, most previous studies have not considered leptin's powerful cardiac effects that are mediated via activation of central nervous system (CNS) leptin receptors (LepRs) which, in turn, elicit major improvements in cardiac metabolism. In this review, we focus mainly on the role of leptin in regulating cardiac function via its CNS LepRs and downstream signaling pathways, such as the brain melanocortin system. Studies from our laboratory showed that CNS LepR activation, without raising plasma leptin levels, has remarkable beneficial effects on cardiac metabolism and function that protect the heart during pathological conditions, including heart failure (HF) induced by myocardial infarction (MI). These cardioprotective effects of leptin appear to be mediated by stimulation of CNS proopiomelanocortin neurons and subsequent activation of melanocortin 4 receptors (MC4R) in the brain. Chronic activation of the brain leptin-melanocortin pathway improves cardiac function and metabolism following myocardial infarction. However, the mechanism underlying this brain-heart crosstalk remains unclear and may have important implications for the development of new therapies for MI and HF. Show less

Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (P Show less