Pigozzi M I
Centro de Investigaciones en Reproducción, Facultad de Medicina, Buenos Aires, Argentina.
Biocell. 1999 Aug;23(2):79-95.
A scheme is proposed to explain the process of sex chromosome differentiation in the class Aves. It is based on the restriction of recombination in an ancestral homomorphic ZW pair and the subsequent degeneration of the non-recombining region of the W chromosome leading to the highly heteromorphic sex chromosomes of carinate birds. The model presented here and Ohno's model of sex chromosome differentiation in Ophidia are the only integral models of sex chromosome evolution based on cytological evidences. The co-existence among living birds of mostly homomorphic (Ratites) and highly heteromorphic ZW pairs (carinates) provides a unique ground to study the mechanisms of sex chromosome differentiation in vertebrates.
提出了一个方案来解释鸟类中性染色体分化的过程。它基于祖先同态ZW对中重组的限制以及随后W染色体非重组区域的退化，导致突胸鸟类高度异形的性染色体。这里提出的模型和Ohno关于蛇类中性染色体分化的模型是基于细胞学证据的仅有的完整的性染色体进化模型。现存鸟类中大多同态（平胸鸟类）和高度异形ZW对（突胸鸟类）的共存为研究脊椎动物中性染色体分化的机制提供了独特的基础。
