top of page

DNA

name (mom)   color    dun   beta casein  kappa  casein  beta lactoglobulin  polled/horn

Abigael (Kira)    ED/e      B/b         A2/A2               A/A                       B/B                          Pc/Pc        Anya (Itsy)         ED/E+    b/b         A2/A2               A/A                       A/B                          Pc/Pc

Ava (Bitsy)         ED/E+    b/b         A2/A2               A/A                       A/B                          Pc/Pc

Bitsy (Wing)       ED/E+    b/b         A2/A2               A/A                      A/B                           Pc/Pc

Dara (Honey)      e/e                       A2/A2               A/A                      A/A                           Pc/Pc

Gilroy (Malin)     E+/e      B/B         A2/A2              A/A                       A/B                           Pc/Pc

Honey (Rose)     e/e                        A2/A2              A/A                       A/A                           Pc/H

Itsy (Wing)          ED/E+    b/b         A2/A2              A/A                      A/B                           Pc/Pc

Kira (carrier)      E+/e       B/b        A2/A2              A/A                       A/B                           Pc/H

Lacy (Malin)        E+/e      B/B        A1/A2              A/A                       B/B                           Pc/H

Mae (Wing)         ED/e      B/B        A2/A2              A/A                       A/B                           Pc/Pc

Rose (Mariah)     e/e                       A1/A2              A/A                       A/A                           Pc/H

Sparky (Ellen)    ED/E+    b/b        A2/A2              A/A                       B/B                           Pc/Pc

Vibrato (Marie)                                A2/A2                                                                             Pc/H

Wing (Rori)         ED/E+    B/b        A2/A2             A/A                        B/B                           Pc/H

Color

ED/ED  Dominant black. This animal cannot produce red offspring

ED/E+  Dominant black, carrier of wild type

ED/e    Dominant black, carrier of recessive red

E+/E+  Wild type red

E+/e     Wild type, carrier of recessive red

e/e       Recessive red. When bred to another 'e/e' will produce only red offspring

b/b       Plus at least one ED it will be dun, without it red

B/b       carries dun

Milk

Based on the aminoacid present in position 67 these variants can be classified into 2 groups - A1 and A2. Variants in the A1-group (Histidine) are A1, B, C, F and G. Variants in the A2-group (Proline) are A2, A3, D, E, H1, H2, I, K and L. The levels of bioactive peptide beta-casomorphin 7 (BCM7) produced from the metabolism of beta casein is several-fold higher for variants in the A1group than in the A2 group. Higher levels of BCM7 have been associated with negative health effects in humans. Relative to levels of BCM7 production,  variants within each group behave similarly but may differ in other properties.

Kappa Casein - protein yield and percentage. The A variant and AA genotype are associated with higher milk production. The B variant and BB genotype are associated with increased milk protein and casein content, and better cheese yield. Relative to protein content and cheese production, BB is the most favorable genotype, AB is intermediate and AA is the least favorable. Cheese from the milk of BB Kappa Casein cows' clots 25% faster & 2x as firm as from AA milk. 

Beta Lactoglobulin - milk yield and whey protein content. The A variant is associated with increased milk yield and whey protein content. The B variant is associated with increased casein and fat content and is favorable for cheese production.

* The beta casein test was redesigned by the VGL to detect other known variants and improve resolution of the A2 genotyping test. 

This change applies to all samples tested since December 9, 2016. 

For more information, please see https://vgl.ucdavis.edu/services/A2Genotyping.php

 

Chondrodysplasia (Chondro or Chondie)

non-carrier bull X carrier cow

        50%/50% calf will be carrier

        no chance of bulldog calf

bottom of page