Biomaterial Database

Multifactorial inheritance of non-syndromic macrocephaly. 1996

L Arbour, and G V Watters, and J G Hall, and F C Fraser

Department of Human Genetics, McGill University, Montreal, Quebec, Canada.

OBJECTIVE To reevaluate previous claims that non-syndromic macrocephaly is usually inherited as an autosomal dominant trait. METHODS Head size was measured in the parents and sibs of children with non-syndromic macrocephaly. METHODS If autosomal dominant inheritance is involved, the frequency distribution should be bimodal. RESULTS Head circumference of parents and sibs of the macrocephalic probands had a mean significantly greater than the population norm, and a unimodal distribution. Probands with psychomotor impairment had bigger heads, and more had a history of birth difficulty, than did unimpaired probands. CONCLUSIONS The usual genetic basis for non-syndromic macrocephaly is multifactorial with a polygenic genetic basis, rather than autosomal dominant. Risk of recurrence appears to be much lower than if it would be on the assumption of autosomal dominant inheritance. Macrocephaly in a parent or sib of an unborn child may present a risk for birth injury to that child. A larger series of patients will be necessary to resolve this question.

UI	MeSH Term	Description	Entries
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D008297	Male		Males
D008607	Intellectual Disability	Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)	Disability, Intellectual,Idiocy,Mental Retardation,Retardation, Mental,Deficiency, Mental,Intellectual Development Disorder,Mental Deficiency,Mental Retardation, Psychosocial,Deficiencies, Mental,Development Disorder, Intellectual,Development Disorders, Intellectual,Disabilities, Intellectual,Disorder, Intellectual Development,Disorders, Intellectual Development,Intellectual Development Disorders,Intellectual Disabilities,Mental Deficiencies,Mental Retardations, Psychosocial,Psychosocial Mental Retardation,Psychosocial Mental Retardations,Retardation, Psychosocial Mental,Retardations, Psychosocial Mental
D010375	Pedigree	The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.	Family Tree,Genealogical Tree,Genealogic Tree,Genetic Identity,Identity, Genetic,Family Trees,Genealogic Trees,Genealogical Trees,Genetic Identities,Identities, Genetic,Tree, Family,Tree, Genealogic,Tree, Genealogical,Trees, Family,Trees, Genealogic,Trees, Genealogical
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
D001720	Birth Injuries	Mechanical or anoxic trauma incurred by the infant during labor or delivery.	Injuries, Birth,Birth Injury,Injury, Birth
D002170	Canada	The largest country in North America, comprising 10 provinces and three territories. Its capital is Ottawa.
D002508	Cephalometry	The measurement of the dimensions of the HEAD.	Craniometry
D004198	Disease Susceptibility	A constitution or condition of the body which makes the tissues react in special ways to certain extrinsic stimuli and thus tends to make the individual more than usually susceptible to certain diseases.	Diathesis,Susceptibility, Disease,Diatheses,Disease Susceptibilities,Susceptibilities, Disease
D005260	Female		Females