In spite of the usefulness of codominant markers in population genetics, the existence of null alleles raises challenging estimation issues in natural populations that are characterized by positive inbreeding coefficients (F > 0). Disregarding the possibility of F > 0 in a population will generally lead to overestimates of null allele frequencies. Conversely, estimates of inbreeding coefficients (F) may be strongly biased upwards (excess homozygotes), in the presence of nontrivial frequencies of null alleles. An algorithm has been presented for the estimation of null allele frequencies in inbred populations (van Oosterhout method), using external estimates of the F-statistics. The goal of this study is to introduce a modification of this method and to provide a formal comparison with an alternative likelihood-based method (Chybicki-Burczyk). Using simulated data, we illustrate the strengths and limitations of these competing methods. Under most circumstances, the likelihood method is preferable, but for highly inbred organisms, a modified van Oosterhout method offers some advantages.

中文翻译：

---

比较van Oosterhout和Chybicki-Burczyk估计自交群体无效等位基因频率的方法。

尽管共有标记在种群遗传学中​​很有用，但无效等位基因的存在在自然种群中提出了具有挑战性的估计问题，这些问题的特征是近交系数为正（F> 0）。忽略种群中F> 0的可能性通常会导致高估无效等位基因频率。相反，在无效等位基因的非平凡频率下，近交系数（F）的估计值可能会强烈向上偏移（纯合子过多）。提出了一种使用F统计量的外部估计来估计自交群体中无效等位基因频率的算法（van Oosterhout方法）。这项研究的目的是介绍这种方法的一种改进，并与基于可能性的替代方法（Chybicki-Burczyk）进行正式比较。使用模拟数据，我们说明了这些竞争方法的优势和局限性。在大多数情况下，似然法是可取的，但是对于高度近交的生物，改良的van Oosterhout方法具有一些优势。