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Normal phenotypic boy with 45X/46XY mosaic



My 10-yr-old son (fraternal twin of genetically normal girl and older brother of genetically normal boy) was diagnosed in utero with 45X/46XY chromosomal mosaic. He was born and continues to appear a completely normal male. His last doctor visit on the topic was to geneticist at 1 yr of age. Physically, he is tall; normal appearance. Mentally, he is gifted, perhaps highly gifted. My understanding is that his biggest risks are gonadal tumors and infertility. My questions are: given his completely normal appearance and lack of symptoms, should we, based on the diagnosis, be seeing a geneticist? If so, when? Is the chance of a problem highest upon onset of puberty? Should we be vigilant about checking for testicular tumors? Is he very likely to be infertile, and is that something we can find out at his age? Thank you in advance for any advice.


Your questions would be best addressesd by a specialist is following your son on a regular basis. You should either return to the medical geneticist whom you saw when your son was first diagnosed or find another medical geneticist. You might also consider seeing an endocrinologist if you are not able to locate a genetics center.

Related Resources:

Society of Genetic Counselors Resource Center

For more information:

Go to the Cancer Genetics health topic.