Asthma tends to run in families, as do related allergic conditions like hay fever and eczema.
Umbefu udle ngokuba sisifo esigqugqisa kwiintsapho, njengoko zisenza izifo ezinxulumene nokwaliwa kwezinto ezithile yimpilo yomntu ezinjengomfixane olubangwa ngumungu (hay fever) kunye nesifo sesikhumba esirhawuzelayo.