Crossed fused ectopia of the kidneys in identical twins occurred. The etiology of this anomaly is obscure but environmental and genetic factors are discussed with special emphasis on animal studies to date.
Greenberg LW, Nelsen CE. Crossed Fused Ectopia of the Kidneys in Twins. Am J Dis Child. 1971;122(2):175-176. doi:10.1001/archpedi.1971.02110020109019