1971年부터 1973年까지 安養에서 採集한 Drosophila melanogaster의 蹄2 染色體上에 保有되어 있는 致死因子, 不姙因子 및 可視突無變異體의 頻度를 調査하였다. 1) 致死 및 反致死因子를 保有하고 있는 染色體의 頻度는 3년간 평균 28.2% 로 나타났고, 3年간의 빈도는 큰 差異가 없었다. 2) 安養自然集團의 致死遺傳因子間의 同座率은 0.77%였다. 致死因子로 이한 集團內에서의 elimination rate $(IQ^2)$는 0.0008로 추정되었다. 3) 第2染色體에 保有되어있는 劣性不姙因子는 암컷 9.1%, 수컷 6.8%, 그리고 兩性不姙이 2%로 나타났다. 4) 劣性可視突然變異體인 rbl/rbl과 bw/bw은 第2染色體에서 동협접합자가 될 때 檢出된다. 本實驗에서 rbl 因子는 2.7%였고 bw 因子는 1.3%로 나타났다.
The frequency of the second chromosomes bearing deleterious genes in the Anyang natural population of Korea in Drosophila melanogaster was repeatedly estimated during the period from 1971 through 1973. 1) The frequency of lethal and semilethal chromosomes was calculated to be 28.2%, and the frequencies were maintained without fluctuation for three years. 2) Allelism rate between lethal genes isolanted from each year was 0.77% on the average. The rate of elimination of lethal genes $(IQ^2)$ was estimated to be 0.0008. 3) The frequency of sterile gene on the second chromosomes was estimated to be 9.1% for females, 6.8% for males and 2.0% for both sexes, respectively. 4) Recessive visible mutant genes, namely rbl and bw genes, were frequently extracted when the chromosomes were revealed in homozygous. The frequencies of these mutants were found to be 1.3% for bw genes and 2.7% for rbl genes, respectively.
