Who are Dwarfs?
Dwarfs and Dwarfism
Dwarfs are adult persons with a short stature of less than 4 feet and 10 inches. They are friendly persons commonly seen at the circus, the fair, at the market and on the street. There are four common types of dwarfs, the cretin, the pituitary dwarf, the african pygmy and the person affected by achondroplasia.
Cretinism develops in infants and children due to lack of thyroid hormone either due to a deficiency of iodine in the diet or a defective or diseased thyroid gland. It causes severe retardation of the physical and mental development and if untreated, there is stunting of growth and the stature attained is that of a dwarf. The skin becomes thick and flabby, the nose is flattened, the tongue is protruded with the abdomen pushed forward. There is slowness of movement and speech with a low I.Q. The childhood cretin develops into the classical Moron, Idiot or Imbecile of an adult.
Pituitary dwarfism is caused due to a dysfunction of the pituitary gland, a pea sized body of tissue situated at the base of the brain, which is the master gland controlling all the other peripheral endocrine glands much like the director of an orchestra. It is divided functionally into an anterior pituitary and a posterior pituitary. Two thirds of the cases of pituitary dwarfism are due to a deficiency of all the anterior pituitary hormones and one third due to an isolated deficiency of one of the hormones responsible for growth called the Growth hormone. These one third cases are perfectly proportioned and mature sexually and can reproduce. ( ' the villainous girl in the hollywood movie, 'Orphan' ! )
The African Pygmy belongs to a subgroup of the second(one third) type of pituitary dwarfism. In them there is an inherited inability to form Somatomedin-C also called Insulin-like growth factor-1 in response to Growth hormone stimulation. At least four somatomedins are recognised which are responsible for the growth of the bone and tissue. Since the pygmies lived in rain forests sheltered from the sun, vitamin D deficiency has also been incriminated in the development of the short stature.
Achondroplasia: Persons affected by this disorder comprise 70% of the dwarfs in the community. They are the familiar dwarfs at the circus, at small stores, on the street etc. The characteristic features are an average sized trunk, short upper arms and thighs, limited motion at the elbow joints and an enlarged head with a prominent forehead. In achondroplasia there is a defect in the conversion of cartilage to bone, particularly of the long bones of the arms and legs resulting in shortening of the limbs. The affected persons are of normal intelligence and lead fruitful lives