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Background: The prevalence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing in South Korea and many parts of the world. However, the genetic factors underlying susceptibility to this disease remain elusive., Methods: To identify genetic variants in patients with NTM-PD, we performed a genome-wide association study with 403 Korean patients with NTM-PD and 306 healthy controls from the Healthy Twin Study, Korea cohort. Candidate variants from the discovery cohort were subsequently validated in an independent cohort. The Genotype-Tissue Expression (GTEx) database was used to identify expression quantitative trait loci (eQTL) and to conduct Mendelian randomisation (MR)., Results: We identified a putatively significant locus on chromosome 7p13, rs849177 (OR, 2.34; 95% CI, 1.71 to 3.21; p=1.36×10 -7 ), as the candidate genetic variant associated with NTM-PD susceptibility. Its association was subsequently replicated and the combined p value was 4.92×10 -8 . The eQTL analysis showed that a risk allele at rs849177 was associated with lower expression levels of STK17A , a proapoptotic gene. In the MR analysis, a causal effect of STK17A on NTM-PD development was identified (β, -4.627; 95% CI, -8.768 to -0.486; p=0.029)., Conclusions: The 7p13 genetic variant might be associated with susceptibility to NTM-PD in the Korean population by altering the expression level of STK17A ., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose: Although two white matter hyperintensity (WMH) probability maps of healthy older adults already exist, they have several limitations in representing the distribution of WMH in healthy older adults, especially Asian older adults. We constructed and validated a WMH probability map (WPM) of healthy older Koreans and examined the age-associated differences of WMH., Methods: We constructed WPM using development dataset that consisted of high-resolution 3D fluid-attenuated inversion recovery images of 5 age groups (60-64 years, 65-69 years, 70-74 years, 75-79 years, and 80+ years). Each age group included 30 age-matched men and women each. We tested the validity of the WPM by comparing WMH ages estimated by the WPM and the chronological ages of 30 healthy controls, 30 hypertension patients, and 30 S patients., Results: Older age groups showed a higher volume of WMH in both hemispheres (p < 0.001). About 90% of the WMH were periventricular in all age groups. With advancing age, the peak of the distance histogram from the ventricular wall of the periventricular WMH shifted away from the ventricular wall, while that of deep WMH shifted toward the ventricular wall. The estimated WMH ages were comparable to the chronological ages in the healthy controls, while being higher than the chronological ages in hypertension and stroke patients., Conclusions: This WPM may serve as a standard atlas in research on WMH of older adults, especially Asians., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Being a carrier of the apolipoprotein E (APOE) ε4 allele is a clear risk factor for development of Alzheimer's disease (AD). On some neurocognitive tests, there are smaller differences between carriers and noncarriers, while other tests show larger differences., Aims: We explore whether the size of the difference between carriers and noncarriers is a function of how well the tests measure general intelligence, so whether there are Jensen effects., Methods: We used the method of correlated vectors on 441 Korean older adults at risk for AD and 44 with AD., Results: Correlations between APOE carriership and test scores ranged from -.05 to .11 (normal), and -.23 to .54 (AD). The differences between carriers and noncarriers were Jensen effects: r = .31 and r = .54, respectively., Conclusion: A composite neurocognitive score may show a clearer contrast between APOE carriers and noncarriers than a large number of scores of single neurocognitive tests.