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63   Science Can't Be Dogmatic
     About Virgin Birth in Man
     The Washington Post, Saturday, September 23, l967

     By common knowledge, fertilization of an egg by a sperm is the
indispensable route by which life is transmitted each generation.
Vestiges of parthenogenesis -- "virgin birth" -- can, however, be
observed in a number of animals.  These remind us not to be too
dogmatic about asserting that it could never occur as a natural
process in man or (more likely still) by the calculated use of some
principles learned from experimental biology.

     Some technicalities have to be remembered.  In many mammals,
the implantation of a fertilized egg into the uterus of a virgin
female is a commonplace surgical operation.  This would certainly
work in man: two women, infertile for different reasons, might
cooperate to mother a child neither could produce alone.  So far
as I know, this experiment has not been reported, but it has surely
been attempted.

     Many fertilized eggs that fail to implant could be recovered and
reimplanted.  However, this is not parthenogenesis, which is the
development of an egg that has not been fertilized.

     The most striking example of natural parthenogenesis has been
studied in turkeys by Dr. M. W. Olsen of the Agriculture Department.
Certain breeds had long been known to lay eggs that, although sterile,
would undergo a limited amount of development.  For many generations,
Dr. Olsen selected hens whose eggs showed progressively greater
capacity for this.

     He eventually produced a flock among whose unfertilized eggs
several per cent hatch out into full-fledged birds.  These are males,
as is expected with birds.  Although themselves fatherless, they
have been used to father new generations of birds and help propagate
this interesting potential for parthenogenesis.

     Just how the genetic makeup of this flock facilitates spontaneous
development is not yet understood.  The presence of fowlpox virus as
well as of a group of genes contribute to it.  We face the most
interesting questions both in basic biology and for its human
application.

     Limited parthenogenetic development has been repeatedly observed
in mammalian eggs, and probably sometimes in man.  The embryos usually
die at a very early stage.  Some of this poor survival may be
attributed to genetic weaknesses of the parent that become exposed
in isolated sets of genes.  In rabbits, chilling the eggs regularly
provokes a limited development.

     In 1939, the late Gregory Pincus -- who later contributed so
significantly to the development of oral contraceptives -- reported
having brought five parthenogenetic rabbits out of a great many to
full term, one surviving to an adult breeding stage.  These
experiments are now regarded rather skeptically, not having been
confirmed in other laboratories so far -- but no comparable efforts
have been made, either.

     In fish and reptiles, parthenogenesis occurs naturally in a
number of forms, usually as an escape hatch for the species if males
are scarce or too widely dispersed.  In amphibia, parthenogenesis
is easy to produce in the laboratory by injecting minute quantities
of cell extracts into unfertilized eggs.

     What about man?  The odds of eventually contriving
parthenogenesis seem very high; we then would need a detailed
consideration of the human purposes it might serve or abuse.  As to
its natural occurrence, a cautious assertion is that it is very rare
-- probably fewer than one per million births.

     In England about ten years ago, Dr. Helen Spurway publicized the
question and Dr. S. Balfour-Lynn studied a number of respondents. One
mother was indeed remarkably similar to her daughter when blood groups
were tested.

     The claim of parthenogenesis was put in doubt by the mother's
rejection of a test skin-graft from the daughter, but more recent
work on graft-compatibility makes this test now seem less decisive
than it once did.

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