Morton N E, Rao D C, Lindsten J, Hultén M, Yee S
Hum Hered. 1977;27(1):38-51. doi: 10.1159/000152850.
By fitting compounds beta distributions to chiasma frequencies the physical map obtained from banded chromosomes has been converted into a chiasma map giving the distribution of observed chiasmata in relation to several hundred cytological bands, assuming proportionality of mitotic and meiotic chromosomes. This is a genetic map if there is a precise correspondence between sites of chiasmata and crossing-over. However, if there is appreciable preanaphase movement of chasmata, then the chiasma map is a serious distortion of the genetic map. Predictions from the chiasma map can be confirmed or refuted only by genetic evidence for which the estimates of this paper serve as initial values to begin maximum likelihood iteration.
通过将化合物β分布拟合到交叉频率上，在假设有丝分裂和减数分裂染色体成比例的情况下，从带型染色体获得的物理图谱已被转化为交叉图谱，该图谱给出了观察到的交叉相对于数百个细胞学带的分布情况。如果交叉位点与交换之间存在精确对应关系，这就是一个遗传图谱。然而，如果交叉在后期前有明显移动，那么交叉图谱就是对遗传图谱的严重扭曲。只有通过遗传证据才能证实或反驳从交叉图谱得出的预测，本文的估计值可作为最大似然迭代开始的初始值。
