High Population Frequency of GNRHR p.Q106R in Malta: An Evaluation of Fertility and Hormone Profiles in Heterozygotes.

Context: The gonadotropin-releasing hormone receptor variant GNRHR p.Q106R (rs104893836) in homozygosity, compound heterozygosity, or single heterozygosity is often reported as the causative variant in idiopathic hypogonadotropic hypogonadism (IHH) patients with GnRH deficiency. Genotyping of a Maltese newborn cord-blood collection yielded a minor allele frequency (MAF) 10 times higher (MAF = 0.029; n = 493) than that of the global population (MAF = 0.003). Objective: To determine whether GNRHR p.Q106R in heterozygosity influences profiles of endogenous hormones belonging to the hypothalamic-pituitary axis and the onset of puberty and fertility in adult men (n = 739) and women (n = 239). Design Setting and Participants: Analysis of questionnaire data relating to puberty and fertility, genotyping of the GNRHR p.Q106R variant, and hormone profiling of a highly phenotyped Maltese adult cohort from the Maltese Acute Myocardial Infarction Study. Main Outcome and Results: Out of 978 adults, 43 GNRHR p.Q106R heterozygotes (26 men and 17 women) were identified. Hormone levels and fertility for all heterozygotes are within normal parameters except for TSH, which was lower in men 50 years or older. Conclusion: Hormone data and baseline fertility characteristics of GNRHR p.Q106R heterozygotes are comparable to those of homozygous wild-type individuals who have no reproductive problems. The heterozygous genotype alone does not impair the levels of investigated gonadotropins and sex steroid hormones or affect fertility. GNRHR p.Q106R heterozygotes who exhibit IHH characteristics must have at least another variant, probably in a different IHH gene, that drives pathogenicity. We also conclude that GNRHR p.Q106R is likely a founder variant due to its overrepresentation and prevalence in the island population of Malta.

Peripheral blood RNA biomarkers for cardiovascular disease from bench to bedside: a position paper from the EU-CardioRNA COST action CA17129.

Despite significant advances in the diagnosis and treatment of cardiovascular diseases, recent calls have emphasized the unmet need to improve precision-based approaches in cardiovascular disease. Although some studies provide preliminary evidence of the diagnostic and prognostic potential of circulating coding and non-coding RNAs, the complex RNA biology and lack of standardization have hampered the translation of these markers into clinical practice. In this position paper of the CardioRNA COST action CA17129, we provide recommendations to standardize the RNA development process in order to catalyse efforts to investigate novel RNAs for clinical use. We list the unmet clinical needs in cardiovascular disease, such as the identification of high-risk patients with ischaemic heart disease or heart failure who require more intensive therapies. The advantages and pitfalls of the different sample types, including RNAs from plasma, extracellular vesicles, and whole blood, are discussed in the sample matrix, together with their respective analytical methods. The effect of patient demographics and highly prevalent comorbidities, such as metabolic disorders, on the expression of the candidate RNA is presented and should be reported in biomarker studies. We discuss the statistical and regulatory aspects to translate a candidate RNA from a research use only assay to an in-vitro diagnostic test for clinical use. Optimal planning of this development track is required, with input from the researcher, statistician, industry, and regulatory partners.

The impact of passive and active smoking on inflammation, lipid profile and the risk of myocardial infarction.

OBJECTIVE: To investigate the effect of passive smoking, active smoking and smoking cessation on inflammation, lipid profile and the risk of myocardial infarction (MI). METHODS: A total of 423 cases with a first MI and 465 population controls from the Maltese Acute Myocardial Infarction (MAMI) Study were analysed. Data were collected through an interviewer-led questionnaire, and morning fasting blood samples were obtained. ORs adjusted for the conventional risk factors of MI (aORs) were calculated as an estimate of the relative risk of MI. The influence of smoking on biochemical parameters was determined among controls. RESULTS: Current smokers had a 2.7-fold (95% CI 1.7 to 4.2) and ex-smokers a 1.6-fold (95% CI 1.0 to 2.4) increased risk of MI. Risk increased with increasing pack-years and was accompanied by an increase in high-sensitivity C reactive protein levels and an abnormal lipid profile. Smoking cessation was associated with lower triglyceride levels. Exposure to passive smoking increased the risk of MI (aOR 3.2 (95% CI 1.7 to 6.3)), with the OR being higher for individuals exposed to passive smoking in a home rather than in a public setting (aOR 2.0 (95% CI 0.7 to 5.6) vs aOR 1.2 (95% CI 0.7 to 2.0)). Passive smoke exposure was associated with higher levels of total cholesterol, triglycerides and total cholesterol:high-density lipoprotein cholesterol ratio compared with individuals not exposed to passive smoking. CONCLUSIONS: Both active and passive smoking are strong risk factors for MI. This risk increased with increasing pack-years and decreased with smoking cessation. Such effects may be partly mediated through the influence of smoking on inflammation and lipid metabolism.