TY - JOUR
T1 - Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study
AU - Von Schantz, Malcolm
AU - Taporoski, Tamara P.
AU - Horimoto, Andréa R.V.R.
AU - Duarte, Nubia E.
AU - Vallada, Homero
AU - Krieger, José E.
AU - Pedrazzoli, Mario
AU - Negrão, André B.
AU - Pereira, Alexandre C.
N1 - Funding Information:
This work was performed at the University of São Paulo. It was supported by an international visiting professorship grant from the University of São Paulo (awarded to JEK on behalf of MvS), by Fapesp grants 2013/17368-0 (to ACP) and 2011/05804-5 (to MP), by CNPq grant 400791/2015-5 (to HV), and by a Banco Santander travel award (to MvS). We are grateful to the study participants for their voluntary and unrewarded participation in this study, and to the study staff in the Corações de Baependi office, particularly Emanuelle Pereira Felisalle. We also wish to thank Jason Ellis for sharing his spreadsheet template, and to Simon N. Archer for permission to show data collected in a previous collaboration.
PY - 2015/8/1
Y1 - 2015/8/1
N2 - Diurnal preference (chronotype) is a useful instrument for studying circadian biology in humans. It harbours trait-like dimensions relating to circadian period and sleep homeostasis, but also has ontogenetic components (morningness increases with age). We used the Morningness-Eveningness questionnaire (MEQ) in the Baependi study, a family-based cohort study based in a small town in Minas Gerais, Brazil. The population is highly admixed and has a cohesive and conservative lifestyle. 825 individuals (497 female) aged 18-89 years (average ± SD = 46.4 ± 16.3) and belonging to 112 different families participated in this study. The average MEQ score was 63.5 ± 11.2 with a significant (P < 0.0001) linear increase with age. Morningness was significantly (P < 0.0001) higher in the rural (70.2 ± 9.8) than in the municipal zone (62.6 ± 11.1), and was also significantly (P = 0.025) higher in male (64.6 ± 10.9) than in female (62.8 ± 11.2) participants. Thus, in spite of universal access to electricity, the Baependi population was strongly shifted towards morningness, particularly in the rural zone. Heritability of MEQ score was 0.48 when adjusted for sex and age, or 0.38 when adjusted for sex, age, and residential zone. The reported MEQ score heritability is more akin to those of previous twin studies than previous family studies.
AB - Diurnal preference (chronotype) is a useful instrument for studying circadian biology in humans. It harbours trait-like dimensions relating to circadian period and sleep homeostasis, but also has ontogenetic components (morningness increases with age). We used the Morningness-Eveningness questionnaire (MEQ) in the Baependi study, a family-based cohort study based in a small town in Minas Gerais, Brazil. The population is highly admixed and has a cohesive and conservative lifestyle. 825 individuals (497 female) aged 18-89 years (average ± SD = 46.4 ± 16.3) and belonging to 112 different families participated in this study. The average MEQ score was 63.5 ± 11.2 with a significant (P < 0.0001) linear increase with age. Morningness was significantly (P < 0.0001) higher in the rural (70.2 ± 9.8) than in the municipal zone (62.6 ± 11.1), and was also significantly (P = 0.025) higher in male (64.6 ± 10.9) than in female (62.8 ± 11.2) participants. Thus, in spite of universal access to electricity, the Baependi population was strongly shifted towards morningness, particularly in the rural zone. Heritability of MEQ score was 0.48 when adjusted for sex and age, or 0.38 when adjusted for sex, age, and residential zone. The reported MEQ score heritability is more akin to those of previous twin studies than previous family studies.
UR - http://www.scopus.com/inward/record.url?scp=84924973820&partnerID=8YFLogxK
U2 - 10.1038/srep09214
DO - 10.1038/srep09214
M3 - Article
C2 - 25782397
AN - SCOPUS:84924973820
SN - 2045-2322
VL - 5
JO - Scientific Reports
JF - Scientific Reports
M1 - 9214
ER -