Semenov Kh Kh, Walker D
Biull Eksp Biol Med. 1983 Mar;95(3):71-3.
Spontaneous embryonic lethality and the recessive lethal gene frequency in the gene pool of noninbred mice and rats of the bioteria of the National Research Center of the Cuba Republic Academy of Sciences were investigated. It was established that the level of spontaneous embryonic lethality among mice increased greatly as compared to that in 1977 and was 40% (versus 20% in 1977). Of this number, 30% falls within the postimplantation period. In noninbred rats, these values constituted 21.4 and 8.1%, respectively. High embryonic lethality among noninbred mice may be determined by genetic causes and the influence of ecological factors. The frequency of recessive lethals among noninbred mice was 28%, that among rats 20.8%. It is characteristic that in both categories, recessive lethals became apparent only in the postimplantation period of embryogenesis.
对古巴共和国科学院国家研究中心生物菌群中非近交系小鼠和大鼠基因库中的自发胚胎致死率及隐性致死基因频率进行了研究。结果表明，与1977年相比，小鼠的自发胚胎致死率大幅上升，达到40%（1977年为20%）。其中，30%发生在着床后阶段。在非近交系大鼠中，这些数值分别为21.4%和8.1%。非近交系小鼠的高胚胎致死率可能由遗传因素和生态因素的影响所致。非近交系小鼠中隐性致死基因的频率为28%，大鼠为20.8%。其特点是，在这两类动物中，隐性致死基因仅在胚胎发育的着床后阶段才显现出来。
