Genetic disorder that can result when sister chromatids fail to separate properly is likely to occur in meta-phase (m-phase) because in mitosis during m-phase there is separation of DNA to two equal halves.
<u>Explanation:</u>
Genetic disorder is the problem that is caused by the abnormal activities in gene.
This is also called mutation which may cause due to error during replication of DNA and also due to some environmental factors such as radiation exposure, smokes.
So, during meta-phase, genes might not separate and genetic disorder might happen.