Section II — Immunogenetics 



behaviour between recipients and implanted 

 ovaries in the different combinations. The more 

 significant differences have been obtained in 

 the survival frequencies; the highest percentage 

 found is 55.1 per cent in the grafts of Chieti — 

 v in tu A2, while the lowest percentage was of 

 1.0 per cent grafting yellow white in tu B3. As 

 regards both development and functionality, 

 the differences are less significant, even if there 

 is significance when the recipient stock is tu B3. 

 The grafts generally are more successful in 

 stock tu A-2 than in tu B 3 and in Varese. Such a 

 different behaviour leads to consider the dif- 

 ferences between the two stocks as a result of 

 behaviour of lymph gland and the number of 

 cells swimming free in the haemolymph. In fact, 

 in tu A2 the number of free cells is high, very 

 low in tu B3 and in Varese. 



to hemolytic disease — this problem is under 

 investigation. 



11.7. Blood Groups of the Domestic Mink. Jan 



Rapacz and Richard M. Shackelford 

 (Krakow, Poland, and Madison, U.S.A.). 



Immunogenetic investigations in the domestic 

 mink (Mustela visori) started in 1961 by Rapacz 

 and Shackelford at the Fur Animal Research 

 Laboratory, University of Wisconsin, have 

 been reported in three papers. (^ At least seven 

 blood factors have been recognized by using 

 reagents from hetero- and iso-immune sera. All 

 reagents functioned as agglutinins and saline 

 agglutination tests were employed for dis- 

 covery of all antigenic factors except the anti- 

 globulin test for D specificity. Thirteen sera of 

 the 790 tested showed normal agglutinins; 

 three anti-A, six anti-B2, one unidentified and 

 three nonspecific auto-agglutinins (these three 

 mink, mother and sons, died). 



A total of 1599 individuals were tested against 

 anti-A, B, B 2 and 428 of them with anti-C 

 also; each mink reacted with one or more of 

 these reagents. Pedigree analysis of 668 off- 

 spring from 171 litters resulting from planned 

 matings indicate that these four specificities are 

 determined by triple alleles. Using the reagents 

 anti-A, B and C, six phenotypes corresponding 

 to the six possible genotypes were identified in 

 this system. Blood factors A, B and C corres- 

 pond with genes A*, A and A c , respectively. 

 The B2 specificity is produced by gene A b as 

 well as by gene A c , and consistently accompanies 

 factors B and C in the mink; a single specificity 

 similar to B has been found in the Stone marten 

 (Martes foina). Reagents in the A system, 

 especially anti-B2, show clear dosage effects. 

 There is slight evidence that the mink is subject 



1. Nature, 196, 4861; Immunogenetics Letter 3 

 (No. 1), 55-61 ; Nature (in press). 



11.8. Full-thickness Skin Grafting in Pigs. L. N. 



Baker and E. Andresen (Ames, U.S.A.). 



Results of full-thickness skin grafting in pigs 

 have demonstrated the anticipated existence of a 

 histocompatibility mechanism. This grafting 

 technique has been introduced in connection 

 with blood-typing to detect animals which 

 are either monozygotic twins or erythrocyte 

 mozaics (natural chimeras). The dorsal surface 

 of the ear provides a suitable graft bed while 

 satisfactory grafts can be taken from the dorsal 

 or ventral side of the ear. A circular cutting tool 

 and a scalpel were used to prepare the graft bed 

 and to excise the graft. An adhesive patch held 

 the graft in place 4 to 6 days. Fifty-six pure- 

 bred pigs from outbred Duroc and Hampshire 

 stock were used. Forty of these were paired as 

 littermates of the same sex and same blood type 

 as detected with twenty blood-typing reagents. 

 Each paired pig received three grafts: an auto- 

 graft; a homograft from its pair-mate; and a 

 homograft from another littermate of the same 

 sex but slightly different blood type (not avail- 

 able to 4 pairs). All autografts were accepted. 

 Four of the homografts exchanged between lit- 

 termates of the same blood type were lost by ac- 

 cident; the remaining 36 were sloughed after 

 37.0 ± 2.5 days. Nine homografts taken from 

 littermates of a different blood type were lost 

 by accident; the remaining 23 were sloughed 

 after 32.7 ± 3.8 days. Although the difference 

 in rejection time is not statistically significant, it 

 suggests an association of blood type with rejec- 

 tion mechanism. Thus, the combined tech- 

 niques have proved satisfactory for routine 

 examinations. 



This work has received assistance from Con- 

 tract AT(1 l-l)-707 from the U.S. Atomic 

 Energy Commission. 



11.9. Gene Interaction and the A-O Blood-group 

 System in Pigs. Benjamin A. Rasmusen 

 (Urbana, U.S.A.). 



Anti-pig-A antibodies are present in normal 

 sera of certain cattle, sheep, and pigs, and anti- 



191 



