Congenital iodine deficiency syndrome degree of iodine deficiency was milder and manifested primarily as thyroid enlargement rather than severe mental and physical impairment. In Switzerland, for example, where soil does not contain a large amount of iodine, cases of congenital iodine deficiency syndrome were very abundant and even considered genetically caused. As the variety of food sources dramatically increased in Europe and North America and the populations became less completely dependent on locally grown food, the prevalence of endemic goitre diminished. The early 20th century saw the discovery of the relationships of neurological impairment with hypothyroidism due to iodine deficiency. Both have been largely
Isobutyryl-coenzyme A dehydrogenase deficiency Isobutyryl-coenzyme A dehydrogenase deficiency Isobutyryl-coenzyme A dehydrogenase deficiency, commonly known as IBD deficiency, is a rare metabolic disorder in which the body is unable to process certain amino acids properly. People with this disorder have inadequate levels of an enzyme that helps break down the amino acid valine, resulting in a buildup of valine in the urine, a symptom called valinuria. Defects in the "ACAD8" gene cause isobutyryl-coenzyme A dehydrogenase deficiency. The "ACAD8" gene provides instructions for making an enzyme that plays an essential role in breaking down proteins from the diet. Specifically, the enzyme is responsible for processing valine,