The direct labeled 1q21 probe is ~548kb in size and is located on chromosome 1q21.3. The 1q21 probe is labeled in CYMO-ORANGE and detects copy numbers of the 1q21.3 region. The 1p21 probe is ~655kb in size and is located on chromosome 1p21.2. The 1p21 probe is labeled in CYMO-GREEN and detects copy numbers of the 1p21.2 region. When the probe is hybridized to a normal cell it will show two orange and two green signals.