Allan, J.L., Robbie, M., Phelan, P.D. et al. Eur J Pediatr (1981) 135: 291. doi:10.1007/BF00442105
A recurrence rate for meconium ileus of 39% was found among C.F. affected siblings in a study of 488 families with at least one C.F. child born over a 24 year period. The recurrence rate was highly significant and indicated a familial trend for the occurrence of meconium ileus. The findings of the study support the existence of genetic heterogeneity in cystic fibrosis.