“Knocking out spo11 in chicken arrests meiosis but does not prevent further development of germ cells”

Knockout of the mouse spo11 prevents double-strand breaks and formation of synaptonemal complex during meiosis. As a result, the development of spermatocytes is arrested at zygotene and the arrested cells undergo apoptosis. Not so in the chicken. Here, although we also observe arrest of meiosis and impaired fertility, diploid spermatocytes and oocytes continue to develop with interesting biological consequences.