Am I Like This?
Genesis, chapter 5, tells us about "the generations of Adam": Adam begat Seth, Seth begat Enosh, Enosh begat Kenan... down to Noah of the flood. Translated into modern genetic terms, the account could read "Adam passed a copy of his Y chromosome to Seth, Seth passed a copy of his Y chromosome to Enosh, Enosh passed a copy of his Y chromosome to Kenan"... and so on until Noah was born carrying a copy of Adam's Y chromosome. The Y chromosome is paternally inherited; human males have one while females have none.
All human cells, other than mature red blood cells, possess a nucleus which contains the genetic material (DNA) arranged into 46 chromosomes, themselves grouped into 23 pairs. In 22 pairs, both members are essentially identical, one deriving from the individual's mother, the other from the father. The 23rd pair is different. While in females this pair has two like chromosomes called "X," in males it comprises one "X" and one "Y," two very dissimilar chromosomes. It is these chromosome differences which determine sex. That's the good news about the Y chromosome. If we didn't have it we would all be females.
However, the bad news is that the Y is very short compared to the X with which it is paired. Until quite recently it was believed that the Y chromosome was becoming ever shorter and some felt that it might lose function all together. However, a 40-strong team of researchers led by Dr. David Page of the Whitehead Institute at the Massachusetts Institute of Technology has found that the Y chromosome is much more important than scientists once believed.
As well as having a previously unknown and elaborate back-up system for self-repair, the Y chromosome also carries 78 genes, almost double the previously known tally, the researchers reported. "The Y chromosome is a hall of mirrors," says Page, whose team has for the first time identified the full genetic sequence of a Y chromosome, from an anonymous donor.
The team believes the Y has developed an apparently unique way of pairing up with itself. They found that many of its 50 million DNA "letters" occur in sequences known as palindromes. Like their grammatical counterparts, these sequences of letters read the same forward as backward but are arranged in opposite directions - like a mirror image - on both strands of the DNA double helix. This means that a back-up copy of each of the genes they contain occurs at each end of the sequence. When the DNA divides during reproduction, the team believes, it opens an opportunity for genes to be shuffled or swapped and faulty copies to be deleted.
Cut this Other chromosomes typically have thousands of genes packed into their DNA. The Y-chromosome, to date, has been found to have only about 20 genes. The XX chromosome that women have helps insure that genetic errors on the X chromosome will be masked by the other X.
Although new discoveries show that the Y chromosome can repair itself better than was once thought, men with only one X and a very small matching chromosome, the Y, are still more susceptible to problems than are females. As a result males suffer more genetic problems than females such as color blindness and muscular dystrophy.
From the moment of conception males are more fragile and vulnerable than females. Male fetuses die more often than female. So do male newborns. So do male infants. So do male adolescents. So do male adults. So do old men.
Part of the explanation is the biology of the male fetus, which is little understood and not widely known. At conception there are more male than female embryos. This may be because the spermatozoa carrying the Y chromosome swim faster than those carrying X. The advantage is, however, immediately challenged. External maternal stress around the time of conception is associated with a reduction in the male to female sex ratio, suggesting that the male embryo is more vulnerable than the female.
The male fetus is at greater risk of death or damage from almost all the obstetric catastrophes that can happen before birth. Perinatal brain damage, cerebral palsy, congenital deformities of the genitalia and limbs, premature birth, and stillbirth are commoner in boys, and by the time a boy is born he is on average developmentally some weeks behind his sister: "A newborn girl is the physiological equivalent of a 4 to 6 week old boy." At term the excess has fallen from around 120 male conceptions to 105 boys per 100 girls.
So we see that right from the moment when that sperm penetrates the egg, males begin to experience problems. Some of us don't make it. We die off early. Others survive to make it into the world, but are at a greater handicap than our female counterparts.
One of the most respected scientists of our times, Ashley Montagu, wrote an entire book aptly titled The Natural Superiority of Women. Written in 1953 and updated a number of times since, he counters sexist claims of female inferiority and offers a host of data from many fields of science to demonstrate that women's biological, genetic, and physical makeup makes her not only man's equal, but his superior in many ways.
In looking at male disabilities we must remember that we are talking about averages. More males will suffer brain damage, for instance, than females. If you are one of those males, you probably find it easy to believe that males are at greater risk than females. However, if you're the mother of a brain damaged daughter, you may feel outraged that we are saying that males are at a disadvantage.
As we go through the ways in which men feel endangered and insecure, remember that we aren't speaking of all men. But we need to recognize the ways in which these underlying issues affect all men's sense of security. We might think of these things as the foundation of manhood. There are many ways in which the foundation itself is weak beginning with weaknesses based on our genetic makeup and extending to our upbringing and socialization.
William S. Pollack, PhD and Ronald F. Levant, EdD have spent a great deal of their professional careers working with males. Dr. Pollack is the co-director of the Center for Men at McLean Hospital and assistant clinical professor of psychology in the Department of Psychiatry at Harvard Medical School. Dr. Levant is dean and professor of Psychology, Nova Southeastern University, Ft. Lauderdale, Florida and founder and former director of the Boston University Fatherhood Project.