A genealogical assessment of heritable predisposition to asthma mortality.
BACKGROUND
Asthma is a multifactorial disease; genetic factors have been suggested but have not been well defined.


OBJECTIVE
This study examined evidence for a heritable component to asthma mortality using a unique data resource consisting of Utah death certificates linked to a genealogy of Utah.


METHODS
Cases were defined as individuals whose death certificate listed asthma as a cause of death in a registry of all Utah deaths since 1904 (n = 1,553). The genealogical index of familiality analysis was used to compare the average relatedness of asthma deaths to the expected relatedness in the Utah population. Relative risks for asthma death in relatives of individuals who died of asthma are provided for close and distant relatives.


RESULTS
The genealogical index of familiality identified a significantly higher average relatedness in cases (P < 0.001), even when close relationships were ignored. In addition, a significantly increased risk of dying of asthma was observed in first-degree relatives of cases (relative risk = 1.69, P < 0.001) and in second-degree relatives of cases (relative risk = 1.34, P = 0.003).


CONCLUSIONS
These results support a heritable contribution to asthma mortality.
Teerlink
Craig C
CC
Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah 84112-5750, USA. craig.teerlink@utah.edu
Hegewald
Matthew J
MJ
Cannon-Albright
Lisa A
LA
D000368:Aged; D001249:Asthma / Q000235:genetics* / Q000401:mortality*; D016208:Databases, Factual; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology*; D006801:Humans; D008297:Male; D010375:Pedigree; D010641:Phenotype; D012189:Retrospective Studies; D018570:Risk Assessment; D014589:Utah / Q000453:epidemiology