There are some estimates that 1 in every 1,000 male children is born a Superman.
So, what exactly is the “Superman syndrome”? What causes it and how does it affect a person?
The Superman Syndrome is caused when the Y chromosomes fail to separate during spermiogenesis (the final stage of sperm formation), resulting in a sperm with two Y chromosomes. Thus, such individuals (typically males) have an extra Y chromosome attached to their two sex chromosomes: XY. Meaning, they have 47 chromosomes in each cell and have the sex chromosome XYY. Thus, the Superman Syndrome in the world of medical science is formally known as 47, XYY syndrome.
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One of the most common effects is faster growth from early childhood. XYY men were found to be taller than the normal man with a height of more than 1.85m or 6 feet.
Some XYY men showed decreased muscle tone, poor writing skills, longer and thicker roots of their permanent teeth, and a higher risk of cardiovascular disease and kidney malformations.
As if affecting the physiology of the body was not enough, the 47, XYY syndrome also undermines the mental capability of the person. Boys with XYY suffer from verbal learning deficiencies due to delayed speech development. Some find it difficult to recall words, understand figurative and metaphorical language, and tend to show ADHD-like attention-related problems.
