About genetic mosaics

Each cell in the human body has bits of genetic material called chromosomes. Most people have the same set of chromosomes in every cell. Sometimes, however, a person has more than one cell line. This is called genetic mosaicism. An error in cell division may result in cells with different genetic codes. Or, two fertilized eggs, rather than resulting in twins, may grow together into a single person. Two of the chromosomes are called sex chromosomes because of their role in helping to determine the sex of a person. Ordinarily a woman has two X chromosomes (XX); a man one X and one Y chromosome (XY). Turner's syndrome occurs when a woman has only a single X chromosome (XO) in each cell. When a person has a Y chromosome in some cells and not others, the resulting condition is called xy-Turners, Mixed Gonadal Dysgenesis, mosaic XY/XO, or simply XY/XO.

About XY/XO mosaics

The overwhelming majority of people who are a mosaic of XY cells (male) and XO cells (Turner's syndrome female) are externally normal males. Approximately 5% are female with Turner's syndrome and approximately 5% are born with ambiguous genitals. XO girls have non-functional 'streak' ovaries. An XY/XO baby may have a streak ovary, a testis, or an ovatestis on either side. The majority of XY/XO babies born with normal male genitals also have normal testes, although they may have reduced fertility. Any XY/XO child may have any of the medical conditions that are more common among girls with Turner's syndrome. These include short stature, heart malformations, and kidney malformations. Whether or not and how a child is affected depends on the distribution of their cell lines during fetal development. Once again, most XY/XO children appear to be normal, healthy boys.

About the xyTurners Support Group

Nearly half of XY/XO babies are aborted. For some XY/XO babies, their parents must decide whether or not to allow cosmetic genital surgery. A few parents have to choose whether to raise their child as a boy or a girl. A few have to decide whether or not to use growth hormones.

We all have opinions, especially when it comes to how other people should raise their children. Yet you’re the ones who have to decide. What we offer is the chance to talk things through with others who’ve been there before you. If you’re considering abortion we’d like to offer you help in placing your baby in a loving family. If the doctors want to remove your baby’s gonads, if they want to operate on their genitals, if you have to choose between pink and blue, contact us. If you want a specialist, if you want medical journal articles, contact us. If you’d like to speak with a parent or an XY/XO adult, contact us. If you just want to talk about it, contact us.

Thank you and may the Lord richly bless you,

Jane Spalding
Corresponding Secretary

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