Mendel ê hoat-chek sī chiàu Gregor Mendel thê-chhut ê kui-chek leh ūn-choán ê ûi-thoân hiān-siōng. Chit-lō kui-chek tāi-seng sī Mendel 1865 nî chì 1866 nî kî-kan hoat-piáu--ê; liáu-āu chi̍t tōaⁿ sî-kan bô sáⁿ liû-hêng, kàu 1900 nî koh hông têng-sin the̍h lâi hoat-tián chò hiān-tāi ûi-thoân-ha̍k ê ki-chhó͘.

Mendel ê hoat-chek siu-kái

 
Ēng Punnett tô͘ piáu-hiān ê Mendel si̍t-giām chi it.

Mendel tùi hôe-liân-tāu si̍t-giām hoat-kiàn nā sī kā sûn khui-hoe pe̍h-sek chéng ê tāu-á kap sûn khui-hoe sī kiô-á-sek ê tāu-á chéng (chia hō chò P sì-tāi) cha̍p-phòe, in sán-seng ê āu-tāi (F1 sì-tāi) sèng-chit m̄-sī P sì-tāi sèng-chit ê saⁿ-lām, sī choân-pō͘ lóng khui kiô-á-sek ê hoe. Nā koh kā F1 the̍h lâi hō͘-siōng kau-phòe, sán-seng ê āu-tāi (F2 sì-tāi) koh pìⁿ chò sī kiô-á-sek pí pe̍h-sek khui-hoe 3 tùi 1 ê pí-lu̍t.

Mendel ê hoan-kiàn ē-tàng ēng āu--lâi kî-tha ha̍k-chiá hoat-tián ê sû-gí lâi chéng-lí chò 3 hāng kui-chek:

  • Hun-lî hoat-chek (Eng-gí: law of segregation), kóng phòe-chú hêng-sêng (gamete formation) ê sî, ta̍k-ê ûi-thoân-chú in ê chē chióng allele, ia̍h chiō sī bó͘ chi̍t-ê ûi-thoân-chú ê bô-kâng piàn-khoán, ē hun-khui, tī bí chi̍t lia̍p phòe-chú kaⁿ-taⁿ thang chûn-chāi chi̍t khoán.
  • To̍k-li̍p hun-phòe hoat-chek (law of independent assortment), kóng phòe-chù hêng-sêng ê sî, bô-kâng sèng-chit (trait) ê ûi-thoân-chú ê kò-pia̍t (to̍k-li̍p) hun-lî.
  • Hián-sèng hoat-chek (law of dominance), kóng ū-ê allele sī hián-sèng (dominant), ū-ê sī ún-sèng (recessive), nā siōng-bô ū chi̍t-ê hián-sèng allele ê seng-bu̍t-thé, i sin-ku-téng sī piáu-hiān hián-sèng allele ê éng-hióng.