Analysis of information sources in references of the Wikipedia article "எக்சு ஒய் ஒய் நோய்த்தொகை" in Tamil language version.
The addition of a Y chromosome to a normal male chromosome constitution does not produce a discernible phenotype. Males with 47,XYY cannot be characterized by discriminating physical or behavioral features. The first diagnosis of this condition, therefore, was a karyotypic and not a phenotypic discovery.
Pubertal development is normal and these men are usually fertile.
