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n. pl. a·syn·ap·ses (-sēz)
The failure of homologous chromosomes to pair during meiosis.


(Biology) biology failure of pairing of chromosomes at meiosis


(ˌeɪ sɪˈnæp sɪs)

n., pl. -ses (-sēz).
failure of the pairing of homologous chromosomes during meiosis.
References in periodicals archive ?
Pachytene asynapsis drives meiotic sex chromosome inactivation and leads to substantial postmeiotic repression in spermatids.
For each control and patient the numbers of pachytene nuclei showing asynapsis, fragmented SC, dotted SC and thin and non-homogeneously stained SC, and the number of pachytene nuclei showing various associations of these abnormalities were quantified.
The most frequent abnormality in patients and controls was fragmented SC, isolated or associated with asynapsis and/or dotted SC.
In addition to these examples of genetic control of chromosome pairing, most cases of asynapsis and desynapsis are best explained as genetic irregularities (mutation?
A distinction should be made between normal meiosis-specific genes driving and regulating the meiotic process and mutated alleles leading to asynapsis or desynapsis.