Mother's genome or maternally-inherited genes acting in the fetus influence gestational age in familial preterm birth.
OBJECTIVE
While multiple lines of evidence suggest the importance of genetic contributors to risk of preterm birth, the nature of the genetic component has not been identified. We perform segregation analyses to identify the best fitting genetic model for gestational age, a quantitative proxy for preterm birth.


METHODS
Because either mother or infant can be considered the proband from a preterm delivery and there is evidence to suggest that genetic factors in either one or both may influence the trait, we performed segregation analysis for gestational age either attributed to the infant (infant's gestational age), or the mother (by averaging the gestational ages at which her children were delivered), using 96 multiplex preterm families.


RESULTS
These data lend further support to a genetic component contributing to birth timing since sporadic (i.e. no familial resemblance) and nontransmission (i.e. environmental factors alone contribute to gestational age) models are strongly rejected. Analyses of gestational age attributed to the infant support a model in which mother's genome and/or maternally-inherited genes acting in the fetus are largely responsible for birth timing, with a smaller contribution from the paternally-inherited alleles in the fetal genome.


CONCLUSIONS
Our findings suggest that genetic influences on birth timing are important and likely complex.
Plunkett
Jevon
J
Department of Pediatrics, Washington University School of Medicine, St Louis, Miss, USA.
Feitosa
Mary F
MF
Trusgnich
Michelle
M
Wangler
Michael F
MF
Palomar
Lisanne
L
Kistka
Zachary A-F
ZA
DeFranco
Emily A
EA
Shen
Tammy T
TT
Stormo
Adrienne E D
AE
Puttonen
Hilkka
H
Hallman
Mikko
M
Haataja
Ritva
R
Luukkonen
Aino
A
Fellman
Vineta
V
Peltonen
Leena
L
Palotie
Aarno
A
Daw
E Warwick
EW
An
Ping
P
Teramo
Kari
K
Borecki
Ingrid
I
Muglia
Louis J
LJ
D044383:Black People / Q000235:genetics; D015331:Cohort Studies; D005260:Female; D016678:Genome / Q000235:genetics*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D009035:Mothers; D010375:Pedigree; D011247:Pregnancy; D047928:Premature Birth / Q000235:genetics*; D044465:White People / Q000235:genetics