title: Familial Aggregation and Heritability of Wuchereria bancrofti Infection.
abstract: The familial recurrence risk of lymphatic filariasis (LF) is unknown. This case study aimed to evaluate the familial susceptibility to infection with Wuchereria bancrofti and to microfilaremia in a village of the Republic of Congo.
  
  
  
  The heritability and intrafamilial correlation coefficients were assessed for both W. bancrofti infection and microfilaremia by controlling for individual risk factors, environmental influence, and household effects.
  
  
  
  Pedigree charts were constructed for 829 individuals, including 143 individuals with a diagnosis of W. bancrofti circulating filarial antigens (CFAs) and 44 who also had microfilariae (MF). There was no intrafamilial correlation regarding CFA levels. However, the presence of MF (ρ = 0.45) and microfilarial density (ρ = 0.44) were significantly correlated among parent-offspring pairs. Heritability estimates for CFA positivity and intensity were 0.23 and 0.18, respectively. Heritability estimates were high for microfilarial positivity (h(2) = 0.74) and microfilarial density traits (h(2) = 0.81).
  
  
  
  Our study suggests that the acquisition of LF is mainly driven by environmental factors and habits and that genetic factors are moderately involved in the regulation of infection. By contrast, genetic factors play a major role in both the presence and intensity of microfilaremia.
authors.affiliation: Institut de Recherche pour le Développement, UMI 233 TransVIHMI Institut national de la santé et de la recherche médicale, U1175 Université de Montpellier.
authors.forename: Cédric B
authors.initials: CB
authors.lastname: Chesnais
authors.affiliation: Institut de Recherche pour le Développement UMR216, COMUE Sorbonne Paris Cité, Université Paris Descartes, Faculté des Sciences Pharmaceutiques et Biologiques, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Sabbagh
authors.affiliation: Institut de Recherche pour le Développement, UMI 233 TransVIHMI Institut national de la santé et de la recherche médicale, U1175 Université de Montpellier.
authors.forename: Sébastien D
authors.initials: SD
authors.lastname: Pion
authors.affiliation: Programme National de Lutte contre l'Onchocercose, Ministère de la Santé et de la Population, Brazzaville, Republic of Congo.
authors.forename: François
authors.initials: F
authors.lastname: Missamou
authors.affiliation: Institut de Recherche pour le Développement UMR216, COMUE Sorbonne Paris Cité, Université Paris Descartes, Faculté des Sciences Pharmaceutiques et Biologiques, France.
authors.forename: André
authors.initials: A
authors.lastname: Garcia
authors.affiliation: Institut de Recherche pour le Développement, UMI 233 TransVIHMI Institut national de la santé et de la recherche médicale, U1175 Université de Montpellier.
authors.forename: Michel
authors.initials: M
authors.lastname: Boussinesq
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002648:Child; D002675:Child, Preschool; D015023:Democratic Republic of the Congo / Q000453:epidemiology; D004781:Environmental Exposure; D005192:Family Health; D005260:Female; D005368:Filariasis / Q000453:epidemiology* / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008842:Microfilariae / Q000302:isolation & purification*; D008875:Middle Aged; D014958:Wuchereria bancrofti / Q000302:isolation & purification*; D055815:Young Adult
keywords: familial aggregation; genetic susceptibility; heritability; lymphatic filariasis