van Nie R, Verstraeten A A
Int J Cancer. 1975 Dec 15;16(6):922-31. doi: 10.1002/ijc.2910160606.
By radioimmunoassay (RIA) mammary tumour virus (MTV) antigens were detected in individual milk samples of C3Hf mice, (female BALB/c X male C3Hf)F1 mice and (female C3Hf X male BALB/c)F1 mice; milk samples of BALB/c mice were negative. In the segregating backcross I population, female BALB/c X male (female BALB/c X male C3Hf) viral antigens were found in the milk of 93 out of 169 mice (55%). In the Bc II population (daughters of Bc I mothers and BALB/c fathers) two groups were distinguished. In the first group, derived from positive Bc I mothers, 55 out of 110 mice (50%) had detectable levels of viral antigens in the milk. In the second group, progeny of negative Bc I mothers, 1 mouse out of 47 was positive. These data are consistent with the assumption that one dominant gene is responsible for the presence of viral antigens in the milk of C3Hf mice. This gene (Mtv-1) seems to be linked with the albino locus situated on chromosome 7; the recombination percentage was about 29. In the first experiment with Bc I mice a significant difference was found between the tumour ages of the mice with virus-positive milk and of the mice with virus-negative milk: all mice (18) with viral antigens in the milk developed mammary tumours at an age ranging from 7 to 18 months, whereas in only 7 out of 16 mice with virus-negative milk were mammary tumours found before the age of 21 months. Viral antigens were detectable (by RIA) in the tumours of mice of both subgroups; however, the amounts (mU/mg tumour) were significantly lower in the tumours derived from mice with virus-negative milk. Although MTV-L of C3Hf mothers could be transmitted to BALB/c mice by foster-nursing, viral antigens could not be detected in milk samples collected prior to the third lactation period; thus an influence on the data of extrachromosomally transmitted MTV-L is unlikely.
通过放射免疫测定法（RIA），在C3Hf小鼠、（雌性BALB/c×雄性C3Hf）F1小鼠和（雌性C3Hf×雄性BALB/c）F1小鼠的个体乳样中检测到乳腺肿瘤病毒（MTV）抗原；BALB/c小鼠的乳样为阴性。在分离回交I群体中，雌性BALB/c×雄性（雌性BALB/c×雄性C3Hf）的169只小鼠中有93只（55%）的乳中发现病毒抗原。在回交II群体（回交I代母鼠与BALB/c父本的子代）中区分出两组。第一组来自阳性回交I代母鼠，110只小鼠中有55只（50%）乳中病毒抗原水平可检测到。第二组是阴性回交I代母鼠的子代，47只中有1只呈阳性。这些数据与以下假设一致，即一个显性基因负责C3Hf小鼠乳中病毒抗原的存在。该基因（Mtv - 1）似乎与位于7号染色体上的白化位点连锁；重组率约为29。在回交I代小鼠的首次实验中，发现乳中病毒阳性小鼠和病毒阴性小鼠的肿瘤发病年龄存在显著差异：乳中有病毒抗原的所有小鼠（18只）在7至18个月龄时发生乳腺肿瘤，而在16只病毒阴性乳小鼠中，只有7只在21个月龄前发现乳腺肿瘤。在两个亚组小鼠的肿瘤中均能检测到（通过RIA）病毒抗原；然而，来自病毒阴性乳小鼠的肿瘤中抗原量（mU/mg肿瘤）显著较低。尽管C3Hf母鼠的MTV - L可通过代乳传递给BALB/c小鼠，但在第三次泌乳期之前采集的乳样中未检测到病毒抗原；因此，额外染色体传递的MTV - L对数据的影响不太可能。
