title: Multiple sclerosis sibling pairs: clustered onset and familial predisposition.
abstract: We evaluated 48 relapsing-remitting multiple sclerosis (R/R MS) sibling pairs derived from 44 families for age and date of onset of MS symptoms, clinical course, and family history of MS. Age- and sex-matched R/R MS clinic patients provided a statistical comparison group. The age of onset tended to cluster within multiplex families. The initial symptom of MS occurred within 5 years of age in 30/48 sibling pairs compared with 16/48 controls. A positive family history of MS (other than siblings) was present in 43% of the multiplex families compared with 20% among simplex controls. In 1st-, 2nd-, and 3rd-degree relatives who had lived into the age at risk, 22/1,134 family members of multiplex sibling pairs had probable or definite MS compared with 10/1,215 control family members. Age of onset clustering in siblings concordant for R/R MS and an increased risk of MS in other family members suggest that factors influencing disease onset may be in part inherited in these kindreds.
authors.affiliation: Neuroimmunology Unit, Massachusetts General Hospital, Boston 02114.
authors.forename: T H
authors.initials: TH
authors.lastname: Doolittle
authors.forename: R H
authors.initials: RH
authors.lastname: Myers
authors.forename: J R
authors.initials: JR
authors.lastname: Lehrich
authors.forename: G
authors.initials: G
authors.lastname: Birnbaum
authors.forename: W
authors.initials: W
authors.lastname: Sheremata
authors.forename: G M
authors.initials: GM
authors.lastname: Franklin
authors.forename: L M
authors.initials: LM
authors.lastname: Nelson
authors.forename: S L
authors.initials: SL
authors.lastname: Hauser
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000235:genetics*; D012307:Risk Factors; D013223:Statistics as Topic