Genetic variations: additional sex chromosomes

• Posted by Hannah Ceridwen Eluned Cavendish-Grosvenor November 14, 2015 Filed in Society Girl's Personal Blogs 1,274 views
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  We are generaly and commonly born with 23 pairs of chromosomes, making  a complimentt of 46 in all. One's sex is determined by the X and Y chromosomes: men have XY and women XX. we are separated by the processes of differentiation and  of sex determination. The development of one's given sex is complex and there are numerous steps which are genetically controlled and regulated. The presence of a Y chromosome invites a dominant tendancy to male phenotype, and the testes develop, under the influence of a testis-determining factor, in or around the 10th week of pregnancy. If the testis-determining factor and the Y chromosome are absent the foetus develops ovaries.

  What most people do not realise is that we can have from 45 to 49 chromosomes. What happens to those who do not conform to the majority 46 chromosomes, including either XX or XY ?

  XXX Females ( 47XXX )

  Healthy, normal, fertile, slender and tall. If there is any defect, it is in learning difficulties, on occasions.

  About 1 in a 1000 live births

  XYY Males ( 47XYY )

  Healthy, normal, fertile and tall. With the igher than average testosterone level, they frequently have Acne.

  Neither of these groups have any idea that they are different.

  My niece has the next variant; and, with diagnosis as an infant, successfult reatment and development she now has 3 girls! Thus proving the textbooks wrong.

  Monosomy 45X ( Turner Syndrome )

  Without diagnosis as an infant and appropriate treatment, there is usually no evidence of female secondary sexual characteristics. Affected individuals are short and stocky, and a few may suffer mental retardation. As these individuals have only one X chromosome and no Y chromosome they are females. 

  About 1 in 3000 live births

  45X is a common variant, but Monosomy 45X is rare

  45Y is also a common variant

  Frequency is 2-3 per 1000 live biths

  46XX males (XX is the standard female )

  These males are only able to produce female children. The abnormality is in a small section of the sex determining region of the Y chromosome.

  46XY females ( XY is the standard male )

  Mutation in the Y chromosome is the cause of females being born XY.

   

  SUMMARY

  I have only touched on the known complexities of Gender and Genetics. I hope I live long enough for precise scientific vindication of why I was born a girl in a male body.

  Thank you for reading this.