Biomaterial Database

Birth weight and natural selection: an example of selection relaxation in man. 1988

L Ulizzi, and C Manzotti

Dipartimento di Genetica e Biologia Molecolare, Università La Sapienza, Roma, Italia.

Differential mortality as a function of birth weight was studied in Japan in the years 1969, 1974 and 1984. During the 15-year interval of observation a progressive equalization of mortality in the birth weight classes near the mean was found both for perinatal mortality as a whole and for its two components, stillbirth and mortality within the 1st week of life. The relaxation of selection on this metric trait is confirmed by the analysis of the variation over time of intensity of selection. A comparison of the Japanese population with other populations so far studied is also presented.

UI	MeSH Term	Description	Entries
D007226	Infant Mortality	Postnatal deaths from BIRTH to 365 days after birth in a given population. Postneonatal mortality represents deaths between 28 days and 365 days after birth (as defined by National Center for Health Statistics). Neonatal mortality represents deaths from birth to 27 days after birth.	Neonatal Mortality,Mortality, Infant,Postneonatal Mortality,Infant Mortalities,Mortalities, Infant,Mortalities, Neonatal,Mortalities, Postneonatal,Mortality, Neonatal,Mortality, Postneonatal,Neonatal Mortalities,Postneonatal Mortalities
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D007564	Japan	A country in eastern Asia, island chain between the North Pacific Ocean and the Sea of Japan, east of the Korean Peninsula. The capital is Tokyo.	Bonin Islands
D008297	Male		Males
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D001724	Birth Weight	The mass or quantity of heaviness of an individual at BIRTH. It is expressed by units of pounds or kilograms.	Birthweight,Birth Weights,Birthweights,Weight, Birth,Weights, Birth
D004812	Epidemiologic Methods	Research techniques that focus on study designs and data gathering methods in human and animal populations.	Epidemiologic Method,Epidemiological Methods,Methods, Epidemiologic,Epidemiological Method,Method, Epidemiologic,Method, Epidemiological,Methods, Epidemiological
D005260	Female		Females
D005313	Fetal Death	Death of the developing young in utero. BIRTH of a dead FETUS is STILLBIRTH.	Fetal Mummification,Fetal Demise,Death, Fetal,Deaths, Fetal,Demise, Fetal,Fetal Deaths,Mummification, Fetal
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man