Thalassemia is a genetic defect that is usually inherited as an autosomal recessive trait. It is found in people of Mediterranean ancestry mainly. In this condition, the person is unable to make one of the globin chains of hemoglobin, or makes a reduced amount of it. The hemoglobin molecules in turn are defective and this leads to anemia. Screening policies in Cyprus reduced the amount of thalassemia cases from 1 out of 158 births to almost zero. In Iran, men are tested first for a premarital screening and if he has microcytosis, or a lowered red cell volume, the woman is tested next. If both show thalassemia, they are referred to a health facility for genetic counseling. Chorionic villus sampling can be done in the 11th week of pregnancy and amniocentesis can be done around the 16th week of pregancy to determine before birth if a baby has thalassemia. Bone marrow transplantation has been available since the 1980's to cure thalassemia, rather than having to depend on blood transfusions.