Genetic effects explain about half the variation in age at menarche, and nonshared environmental factors account for the rest, according to a new study.
Genetic effects explain about half the variation in age at menarche, and nonshared environmental factors account for the rest, according to a study of related pairs of women with different combinations of shared genetic, environmental, and childhood factors.
British researchers examined familial concordance for age at menarche in 25,970 women who had at least 1 first- or second-degree relative also enrolled in the study. Participants included mother-daughter pairs, monozygotic twins, dizygotic twins, half-sisters, grandmother-granddaughter pairs, and aunt-niece pairs.
Heritability accounted for an estimated 57% of the variation in age at menarche in the study population. A woman's age at menarche was strongly related to that of her first-degree relatives. Associations for second-degree relatives were weaker.
Morris DH, Jones ME, Minouk MJ, Ashworth A, Swerdlow AJ. Familial concordance for age at menarche: analyses from the Breakthrough Generations Study. Paediatr Perinat Epidemiol. 2011;25(3):306-311.
Continuous glucose monitors ease care for parents of young children with T1D
December 5th 2023Continuous glucose monitors have been found to improve sleep for parents of young children with type 1 diabetes and may help alleviate the care burden associated with the condition, according to a study conducted in France.
AAP cautions against low-carbohydrate diets for children at risk for diabetes
December 1st 2023According to the American Academy of Pediatrics (AAP), it is recommended that 45% to 65% of total daily calories come from carbohydrates, though very low-carbohydrate diets allow for 20 to 50 grams per day.