Development of polydactylous quail as an animal for studying morphogenesis

遗传性多重畸形(HMM)是日本鹌鹑(Coturnix Japan Onica)的一个新突变，由常染色体隐性基因控制。提出的突变基因的基因符号是HMM。大多数纯合子在孵化第6天死亡，其余在孵化15天在不同阶段死亡。存活到胚胎晚期的纯合子明显缩短了上下喙的距离，呈早期胚状体型，有羽芽，但没有胚珠。此外，它们的前肢和后肢都表现为多指并指。在纯合子的腹部，胃、肝和小肠的一部分从脐部伸出。在HMM晚期胚胎的骨骼中，骨化一般延迟，并在全身观察到形态发生异常。这个突变体似乎成为形态发生研究领域中一个强大的动物模型。

Hereditary multiple malformation (HMM), a new mutation of Japanese quail (Coturnix japonica), is controlled by an autosomal recessive gene. The proposed gene symbol for the mutant gene is hmm. The majority of the homozygotes die at the 6th day of incubation, and the remainder dies at various stages by 15 days of incubation. The homozygotes surviving to the late embryonic stage have greatly shortened lower and upper beaks set apart and show an early-embryo-like body shape, with feather buds but no plumules. Furthermore, they show syndactylous polydactyly in both fore and hind limbs. In the abdomen of the homozygote, a part of the ventriculus, liver, and small intestine protrudes out of the umbilicus region. In the skeleton of the late HMM embryos, ossification is generally delayd, and morphogenetic abnormalities are observed all over the body. This mutant seems to become a powerful animal model in the research fields for morphogenesis.