10 March 2005

Chromosome XXY baby

BABY A was a boy, the doctor thought – tests had shown that it had the male XY chromosome.

But when it was born, the father took one look and fainted.

The baby looked like a perfectly normal girl.

The doctor was equally shocked, as he had been telling the parents how their “son” was doing. “What have I done?” he asked himself.

This baby was one of two such cases delivered in the past six years by Associate Professor Arijit Biswas, head of foetal maternal medicine at the National University Hospital (NUH).

The hospital re-checked all the tests done to make sure there was no mix-up.

There wasn’t. But it took weeks for the parents to be reconciled.

“They were angry, shocked and in rejection,” recalled Prof Biswas.

Their baby had a medical condition called genital anomaly.

It affects one in 5,000-10,000 babies – which means between 400 and 800 people here probably have this problem.

A girl may be born with what looks like a scrotum and penis, or a boy may have almost none of the external organs normal in males.

Baby A would have been accepted as a girl had it not been for the test on the pregnant mother.

The truth may have emerged only at puberty when menstruation failed to occur.

Such babies usually grow up to be extremely attractive and very feminine girls, Prof Biswas said.

In the vast majority of cases, anomalies are obvious to the doctor who carries out routine checks on the baby, said Associate Professor K. Prabhakaran, chief of paediatric surgery at NUH.

A chromosome test verifies the baby’s sex – girls have the XX chromosome, and boys have XY. But in some cases, the chromosomes are garbled – such as XXY, or some XX and some XY.

The recent case of the Zimbabwean sportswoman who was “exposed” as a man, and who said she had been born a woman and intended to be one again, could have been due to an excess of testosterone, said Prof Prabhakaran.

This could have made her female genitalia appear like male organs.

In her case, neither the judge not the hospital which checked her could say for sure what gender she is.

Excess testosterone production, the cause of most genital anomalies, is the easiest problem to deal with, as the “male” organs can be removed with a series of operations.

However, hormonal imbalance will persist and has to be corrected with regular medication.

Foetuses begin life as females. At eight to 12 weeks, the Y gene in boys starts working to develop the testes and produce testosterone, which turns the clitoris into a penis.

It also produces other hormones that shrink female organs like the fallopian tubes, uterus and vagina.

Things can go wrong here, said Prof Prabhakaran. Even if the chromosomes are fine, they may not produce enough hormones. Or the hormones may be present but the body may not read them correctly.

In Prof Biswas’ other case, the mother was distraught and the father was furious, insisting the doctors were trying to pass his son off as a girl.

But they finally accepted it.

“Making a diagnosis and remedying the problem are very different,” said Prof Prabhakaran.

“It’s very difficult to make a male. It’s much easier to make a female if the organs are not adequate.”

To make a boy, doctors carry out reconstructive surgery to give him male organs. But he will lack erectile tissue and hence will not be able to have an erection.

If a boy is just a few weeks old, and cannot be turned into a functional male, the parents and doctor may decide to make him female, by removing the male organs and suppressing testosterone production. – The Straits Times/Asia News Network

Wow.... XXY chromosome baby.... heh.... A girl or a boy? Well that needs some time to guess it out.

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