Pelliniemi L J, Lauteala L
Hum Genet. 1981;58(1):64-7. doi: 10.1007/BF00284151.
Differentiation of gonads in embryonic pigs (ages 24 to 44 days) was studied by light and electron microscopy. Incipient short cord-like structures were seen in embryos of both sexes at the age of 24 days. The cords were ultrastructurally similar. Medullary cords appeared in the testis at 26 days and in the ovary at 28 days. The cords in the ovary degenerated gradually and new cortical cords started to develop at 34 days. The formation of cords in both sexes is difficult to explain with the H-Y antigen theory, according to which the antigen should organize cords only in the male. The present results indicate that new approaches are needed for further development of the H-Y antigen theory.
通过光学显微镜和电子显微镜研究了胚胎猪（24至44日龄）性腺的分化。在24日龄的两性胚胎中均可见到初期的短索状结构。这些索在超微结构上相似。髓索在26日龄时出现在睾丸中，在28日龄时出现在卵巢中。卵巢中的索逐渐退化，新的皮质索在34日龄时开始发育。两性中索的形成很难用H-Y抗原理论来解释，根据该理论，该抗原应该只在雄性中组织形成索。目前的结果表明，H-Y抗原理论的进一步发展需要新的方法。
