Auricular Septal Defect in One of Monozygotic Twins

Abstract

Auricular septal defect is reported in 1 monozygotic twin girl, aged 6 yrs., her twin being clinically normal. The analysis of zygosity is based upon consideration of the fetal membranes, the blood groups and types, the digital, palmar, and plantar configurations and other physical features. The 2 individuals came to differ in their characterization because of a variation in their experience subsequent to conception, such as differences in their circulation in early pregnancy or some random physico-chemical variation in their embryonic development.