A high level of MCH itself doesn't cause symptoms and might only be found with a blood test. If you do have symptoms, they would be related to the condition that caused the high MCH levels. For example, if you have liver disease, you might have pain in the upper part of your abdome...
and environmental agents. Many of the alleles associated with health problems are likely to have low penetrance, meaning that only a few of the individuals carrying them will develop disease. However, because such polymorphisms are likely to be very common in the population, they make a significan...