©@ 1769 ADULT HYPERTHYROIDISM December 1967 TABLE 3. Genes in common (30) Proportion of genes in common Relationship to a given subject ; totale Identical twin Parent, child, sib Fraternal twin which LATSis but one. There is no doubt (31, 32) that there are many auto-immune phenomena associated with Graves’ disease on a familial or inherited basis. re) Ch opwin Grandparent, grandchild, uncle, aunt, nephew, niece, half-sib | First cousin Second cousin been similar to that of Dr. Kriss in this regard. It seems that the genetic abnormality is the inheritance of a predisposition to the formation of auto-immune antibodies, of have Graves’ disease, on the basis of a multifactorial concept? Would one expect negative LATS titers, or would one expect a fair numberof positive titers? @ DR. HSIA: If one is dealing with something that is probably close to the primary gene effect, then one would expectrelatives to show such changes. I don’t know of any data on this subject. However, I would think that if LATS represents a fairly remote effect, then one would probably not be able to detect any such chemical consequence. It is not necessary that it appear. DR. WERNER: Dr. McKenzie and Dr. Kriss, have you any information about relatives and LATS? DR. JOSEPH KRISS, DR. McKENZIE: Department of Radiclogy, Standford University School of Medicine, Palo Alto: We have not done an extensive study of this point. On occasion, when we have had a LATS-positive patient, we have examined the euthyroid relatives and have not. yet found a positive test in any of them. Our experience has DR. SIDNEY H. INGBAR, Department of Medicine and Thorndike Memorial Laboratory, Boston City Hospital, Boston: In relation to the LATS problem and the genetic implications of some unpublished observations that Dr. Freinkel and I made a number of years ago, one thing that confuses me is that, in studying the thy- roid function in a group of relatives of patients with active diffuse toxic goiters, we found about 20% with elevated thyroidal uptakes of '#I. When we analyzed the nature of the relationship of increased uptake relative to the patient, the result was much the same as Dr. Hsia suggested it might be. Siblings showed a higherincidence of abnormal uptakes. However, virtually all of these patients showed suppressible thyroid function with exogenous hormone. I am not quite sure we can equate the presence of LATS with lack of suppression, but possibly we can. I would like to think that might be the case, and therefore we asked ourselves why the uptakes were elevated in this 20% of relatives, in the absence of LATS. The other surprisingly frequent finding was that there was some disturbance of turnover of thyroxine peripherally. Many of the relatives had an accelerated turnover rate with half-times of 42 to five days, TABLE 4. Fingerprint ridge counts: resemblances between relatives (30) Relationship Identical twins Fraternal twins @:2 ~ Parent-child Husband-wife No.of Observed pairs correlation 80 0.95 40.01 642 0.49 +0.04 92 602 149 0.49 +0.08 0.50 +0.03 0.05 +0.08 Theoretical correlation +1.0 +0.5 +0.5 +0.5 0