Detection of monosomy 7 in a patient with otherwise typical AA and failed cytogenetic examination due to lack of evaluable metaphases. SNP-A karyotyping was performed at 2 time points during the course of disease: at presentation (normal male karyogram) and at 12 months (noninformative cytogenetic examination). In general, the total copy number is around 2N (left). The second SNP-A karyotyping (right) demonstrates the deletion of one arm of chromosome 7, shown here as reduction of copy number (2N to 1N).