A<unk> le<unk> ,<unk> l anomaly,<unk> l aberration,<unk> l mutation, or<unk> l disorder, is a missing, extra, or irregular portion of<unk> l DNA. These can occur in the form of numerical<unk> es, where there is an atypical number of<unk> s, or as structural<unk> es, where one or more individual<unk> s are altered.<unk>  mutation was formerly used in a strict sense to mean a change in a<unk> l segment, involving more than one gene.<unk>  anomalies usually occur when there is an error in cell division following meiosis or mitosis.<unk> es may be detected or confirmed by comparing an individual's karyotype, or full set of<unk> s, to a typical karyotype for the species via genetic testing.
Chromosome abnormality
Sex chromosome anomalies
Anatomical pathology
Birth trauma 
Birth trauma
Endocrine disease
Birth defect
Birth injury