In West Bloomfield, Michigan, Alana Saarinen is, by all accounts, a
normal healthy teenage girl who enjoys playing the piano and reading
books. But there's one big difference between her and most people,
because each one of her body's cells contains DNA from three different people [sources: Weintraub, Pritchard].
Alana was conceived in 2000 through a special type of in vitro fertilization
(IVF) called cytoplasmic transfer, which was developed to enhance
fertility in women who had been unsuccessful at conceiving through IVF.
Her parents Sharon and Paul Saarinen contributed the egg and sperm. But
in addition, doctors inserted a small amount of cytoplasm, a gel-like
cellular material from a third woman's egg as well. That process also
passed along some of the donor's mitochondrial DNA, which helped to fix
genetic problems that can prevent a pregnancy [sources: Shoot, FDA, Weintraub].
Alana
isn't the only child born through three-parent IVF. After cytoplasmic
transfer was pioneered by Dr. Jacques Cohen, a New Jersey-based
fertility specialist, by various accounts between 30 and 100 children
were born as a result of the procedure [sources: Weintraub, Levy et al.].
But in 2001 the U.S. Food and Drug Administration (FDA), which feared
that altering the genetic makeup of children might be too risky, told
clinics that they couldn't perform the procedure anymore without
undergoing elaborate regulatory requirements [source: FDA]. Some critics also argued that mixing the DNA from two different women was unethical [source: Weintraub]. All of the clinics stopped performing three-parent IVF (alternately called three-person IVF).
But
in recent years, there's been a resurgence of interest in cytoplasmic
transfers and other forms of three-parent IVF. As the examples of Alana
and other healthy children have shown, having three biological parents
doesn't seem to have the sort of scary risks that naysayers feared. And
as proponents point out, the mitochondrial type of DNA from donors
doesn't play any part in determining what we usually think of as a
person's inherited traits like appearance and abilities [source: Malik].
And
besides helping with conception, the donor mitochondrial DNA, whose
function is to help cells run properly, has another potentially valuable
attribute. It can help prevent more than 50 different genetic diseases,
all of which would be otherwise incurable. Some of these conditions can
cause problems such as muscle weakness, seizures, blindness, deafness,
organ failure and even death [sources: Malik, Lupkin].
For
those reasons, Great Britain became the first nation in the world to
officially legalize three-parent IVF in early 2015 [source: Malik].
And in the U.S., government regulators are taking another look at
three-parent IVF's potential for preventing serious diseases in children
[source: CGS].
So there's an increasing possibility that in the near future, more
children will be born who technically do have three parents.
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