What appears to be a good animal model for 80% of cases of human congenital hypothyroidism is being studied intensively at The Jackson Laboratory, Bar Harbor, Me, and a dozen or so other laboratories.
Wesley Beamer, PhD, a staff scientist at The Jackson Laboratory, first discovered the mutation around the end of 1975 in a female laboratory mouse, although he first thought it was a deficiency of growth hormone. Further breeding of the mouse and its progeny led to the conclusion that the phenotype was due to an autosomal recessive gene. Eva Eicher, PhD, also of the laboratory, then mapped the gene to chromosome 12 in the mouse. (The gene or genes that may be related to some or all cases of human congenital hypothyroidism have not been mapped.)
Thyroid glands in the affected (hyt/hyt) mice are of small size and very hypoplastic, similar to those in 80% of infants