Complete Blood Count (CBC): What This Test Checks and What Your Results Mean

A complete blood count, or CBC, is a common blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets. It gives your doctor a broad picture of your overall health and helps screen for many conditions, such as anemia, infections, and blood disorders, often before symptoms appear.

The BBS10 gene targeted mutation analysis is a specialized genetic test that looks for specific changes (mutations) in the BBS10 gene. This gene is one of over 20 genes known to cause Bardet-Biedl syndrome (BBS), a rare inherited disorder that affects multiple parts of the body. The test uses molecular genetics methods to identify whether there are pathogenic variants in the BBS10 gene that could explain a patient's symptoms.

A small sample of blood is drawn from a vein, usually on the inside of your elbow or the back of your hand. A healthcare provider cleans the skin, places a band around your upper arm, and collects the sample into a tube. The procedure takes only a few minutes, and you may feel a quick sting when the needle is inserted. The sample is then sent to a laboratory for analysis, and you can usually return to your normal activities right away.

A blood sample is typically collected from a vein in your arm. In some cases, other tissue samples may be used. The sample is then sent to a specialized laboratory where technicians analyze the DNA from your cells to look for specific mutations in the BBS10 gene. The test does not evaluate the entire gene but targets known disease-causing mutations.

Your doctor may order a CBC as part of a routine checkup, to help find the cause of symptoms such as fatigue, weakness, fever, easy bruising, or unexplained weight loss, to monitor a condition you already have, such as anemia or a chronic infection, or to see how treatments like chemotherapy or certain long-term medications are affecting your blood cells over time.

Your doctor may recommend this test if you or your child show symptoms of Bardet-Biedl syndrome, which may include: vision problems (especially night blindness and loss of peripheral vision), obesity, extra fingers or toes, kidney abnormalities, learning difficulties, or hearing loss. The test helps confirm or rule out BBS10-related Bardet-Biedl syndrome as the cause of these symptoms.

Your results show whether the levels of your red blood cells, white blood cells, and platelets fall within the normal range. Values that are too high or too low can point to conditions such as anemia, infection, inflammation, dehydration, or problems with clotting. An abnormal result does not always mean a serious illness, so your doctor will look at the numbers together with your symptoms, medical history, and other test results before deciding if more testing or treatment is needed.

A positive result means a pathogenic mutation was found in the BBS10 gene, supporting a diagnosis of Bardet-Biedl syndrome. A negative result means no known BBS10 mutations were detected, but it does not completely rule out Bardet-Biedl syndrome, as other genes may be involved. Your doctor or a genetic counselor will help explain your specific results and what they mean for your care.