Globulin is a protein in the blood. Some of the globulin in the blood is produced by the liver and some is produced by the immune system. These proteins fight infection and transport nutrients. There are three main groups of globulins called alpha, beta and gamma globulins. Certain gamma globulins are immunoglobulins which are produced by the immune system and are named lgM component, lgG component and lgA component.

NORMAL LEVELS

Serum globulin: 2.0 to 3.5 g/dL (grams per one-tenth of a liter)
IgM component: 75 to 300 mg/dL (milligrams per one-tenth of a liter)
IgG component: 650 to 1850 mg/dL (milligrams per one-tenth of a liter)
IgA component: 90 to 350 mg/dL (milligrams per one-tenth of a liter)

LOWER THAN NORMAL LEVELS

Lower than normal levels of globulin can indicate:

Kidney infection

Kidney disease

Hemolytic anemia (Low red blood cells due to destruction of red blood cells prematurely)

Protein deficiency

Liver disease

Decreased immune functions

Celiac disease (Stomach disorder)
Inflammatory bowel disease

HIGHER THAN NORMAL LEVELS

Higher than normal levels of globulin can indicate:

Kidney disease

Types of Cancer
Rheumatoid arthritis
Lupus (Severe and painful inflammation of the skin)

Severe infection

Myeloma (Malignant tumor in bone marrow)