Download Chromosomes and Sex

Basics of Genetics and Female Foeticide
Guru Nanak asserted that women are not at all inferior to men:
"From the woman is our birth, in the woman's womb are we shaped;
To
the
The
woman
woman
is
we
our
are
engaged,
friend
and
to
the
from
the
woman
we
woman
is
are
the
wedded;
family;
If one woman dies, we seek another, through the woman are the bonds of the
world;
Why
call
woman
evil
who
gives
birth
to
kings?
From the woman comes the woman, without woman there is none;
O Nanak, God alone is the one Who is independent of the woman (because He is
unborn)."
Historically, women have been held responsible (blamed!) for not producing the son.
Are women responsible for the sex of the child? Which parent actually determines the
gender of the child? One of the most fundamental decisions during embryonic
development is whether to develop as a male or female. It is therefore surprising that
such an important decision is so flexible in evolutionary terms. The primary triggers
for sex determination can be as diverse as a dominant gene in the Y chromosome
which comes from the man, dosage of the sex chromosomes relative to autosomes,
ploidy, temperature, pheromones or bacterial infections. Major challenge is to
understand how one mechanism changes to another in relatively short evolutionary
times. To understand this, first we have to know about the genetics.
GENETICS
Have you ever wondered why you have the same eye colour as your mother or the
same hair colour as your father? Genetics is the study of heredity or inheritance.
Genetics helps to explain how traits are passed from parents to their young. Parents
pass traits to their young through gene transmission. Genes are located on
chromosomes and consist of DNA. They contain specific instructions for protein
synthesis.
In 1865 a monk named Gregor Mendel in Austria proposed that hereditary traits
passed from parents to offspring were the result of unseen “factors” that contained the
information from generation to generation. Mendel came to the conclusion by
crossbreeding pea plants. For his initial work with the pea plants, which was
substantial for the time and holds true in many cases for modern genetics, Gregor
Mendel is credited as the founder of genetics.
After Mendel’s proposal it was later discovered that the “factors” were located in the
nuclei of cells, in bands called chromosomes. Specific traits, such as blue eyes or
purple flowers, as in Mendel’s garden peas, are located in short stretches on the
chromosomes. One chromosome will contain many genes and together these hold all
of the developmental information of every living organism. Genetics is the study of
genes and chromosomes, their translation and inheritance. Although that definition
appears simple it has proven very complex and highly useful. Genetics has become an
invaluable tool for fighting various diseases; it is used in courtrooms to defend or
condemn suspects, and it has also made its way into archaeology and zoology.
How Do Genes Work
Genes are made of four different nucleotide bases. A nucleotide is a molecule
composed of a nitrogen base, a phosphate group, and a sugar. The four bases are
adenine, thymine, guanine, and cytosine. Adenine (A) is always paired with thymine
(T). Cytosine (C) is paired with guanine (G). Strung out together these bases form two
strands in a double helix like a twisted ladder.
On a chromosome genes are wound tightly, like thread over a spool. When a cell
prepares to divide it unwinds the genes from their positions on the chromosome and
splits the strands apart. Because adenine always bonds with thymine and guanine with
cytosine the cell can remake the gene strands, copying them exactly. If one strand
reads AATTCGCG then the enzymes in the cell will create a complementary strand to
read TTAAGCGC.
Cells draw on genetic information to produce proteins. To do this the cell unwinds the
DNA and transcribes it into mRNA, messenger RNA, which is processed by the cell
as instructions for making protein.
Chromosomes and Sex
Chromosomes are long, stringy aggregates of genes that carry heredity information.
They are composed of DNA and proteins and are located within the nucleus of our
cells. Chromosomes determine everything from hair colour and eye colour to sex.
Whether you are a male or female depends on the presence or absence of certain
chromosomes.
The human species has 23 pairs of chromosomes, 22 pairs of autosomes appear the
same and one pair of sex chromosomes. The sex chromosomes are the X chromosome
and the Y chromosome. If you are a male, you have the standard 22 pairs, plus one X
and one Y chromosome. If you are a female, you will have the standard 22 pairs, plus
two X chromosomes. Presence of these X and Y chromosomes determines the sex of
the offspring. Chromosomes contain the genetic codes that determine our physical
appearance and how we function as a living being. The genetic code is contained
within a molecule commonly referred to as DNA (deoxyribonucleic acid). In the
1980's scientists discovered that the genetic code contained within chromosomes does
not always direct the synthesis of cell products, but contained highly variable regions
of "nonsense" DNA. It was later discovered that these regions could be used as
markers for the identification of individuals. The use of these DNA markers in
criminal forensics is common throughout the world today.
Sex Chromosomes
In human sexual reproduction, two distinct gametes fuse to form a zygote. Gametes
are reproductive cells produced by a type of cell division called meiosis. They contain
only one set of chromosomes and are said to be haploid. The male gamete, called the
spermatozoan, is relatively motile and usually has a flagellum. The female gamete,
called the ovum, is non-motile and relatively large in comparison to the male gamete.
When the haploid male and female gametes unite in a process called fertilization, they
form what is called a zygote. The zygote is diploid, meaning that it contains two sets
of chromosomes.
The male gametes or sperm cells in humans and other mammals are heterogametic
and contain one of two types of sex chromosomes. They are either X or Y. The female
gametes or eggs however, contain only the X sex chromosome and are homogametic.
The sperm cell determines the sex of an individual in this case. If a sperm cell
containing an X chromosome fertilizes an egg, the resulting zygote will be XX or
female. If the sperm cell contains a Y chromosome, then the resulting zygote will be
XY or male.
A Y-chromosome is the sex chromosome found only in males. The two types of sex
chromosomes, X and Y, determine the sex of an embryo. Women have two X
chromosomes and men have an X and a Y chromosome. Because of this, the sex of
the child is determined by which chromosome the male passes down. At
approximately the eighth week of prenatal development, the Y-chromosome triggers
the development of male sex organs.
A crucial event that determines whether the embryo will develop into a male or
female occurs in the second half of week six of the foetus development. If the Y
chromosome is present in the embryo's cells, a gene within the short arm of the
chromosome called sex-determining region (SRY) will turn on, initiating a chemical
chain reaction that will turn on other genes and stimulate the production of male
hormones. If the X chromosome is present, or if the SRY gene is missing from the Y
chromosome, the embryo will develop into a female via mechanisms that are not fully
understood.
The Y chromosome, like the other 22 pairs within the cell, also contains non-coding
variable regions of DNA. These regions have been rigorously studied and the data
generated has proven extremely useful in population studies. It has been discovered
that there is significant variability within the polymorphic regions of the Y
chromosome between populations, but there is little or no variability between father
and son. The Human Genome Project has given us an invaluable tool for the
verification of male lineage.
FEMALE FOETICIDE AND INFANTICIDE IN INDIA
Among various women related issues in India, the female foeticide and female
infanticide has become one of the social problems. There is a belief regarding the
nature of men and women: "Men are ritually pure, physically strong, and emotionally
mature; women, on the other hand, are ritually pollutable, physically weak, and lack
strong willpower." Because of these beliefs parents are unwilling to invest time on
daughters. The advent of technology and misuse of pre-natal sex detection and also
attitude of the unscrupulous medical practitioners, who are facilitating the female
foeticide through induced abortions. There are strict laws and penal actions against
violators, but the laws have not worked. Over 10 million female foetuses have been
aborted in India in the past two decades.
The sex ratio as per 2001 census the females are 933 per 1000 males. Although a
marginal improvement in the overall female to male sex ratio in India from 1991 to
2001 is an encouraging development. It is pertinent to note that the figures show the
fall in the juvenile sex ratio is much higher in the economically developed States in
India. There is steep fall in sex ratio in States like, Punjab, Haryana, Gujarat and
Maharashtra, along with the Union territories of Delhi and Chandigarh. In Punjab
there are only 874 females per 1,000 males. The situation in Haryana, Gujarat and
Maharashtra is also similar - the females are 861, 921 and 922 respectively per 1,000
males. Kerala is the only State where females are 1,058 per 1,000 males.
In India the reason behind in rise of female foeticide is because of the strong son
preference in society, universalisation of the small family norm, practices like
tradition of giving dowry, laws that govern property inheritance and the cultural
perception about the familial name through the male line. The mortality of girl child is
also high because of parental discrimination against their daughters in terms of health
care and nutrition.
According to a recent report by the United Nations Children's Fund up to 50 million
girls and women are missing from India's population as a result of systematic gender
discrimination in India. There are instances like, leaving days old girl-child near the
gates of Governmental Health Centres, Juvenile Centres, Temples and Churches
leaving baby's fate to God. Selling girl child for few hundred rupees to childless
couples is another atrocity.
Several Incentives and Schemes were introduced by the Government of India to
reduce Infant Mortality Rate in India and to discourage the practice of female
infanticide. To combat the situation Government of India had enacted Pre-natal
Diagnostic Techniques (Regulation and Prevention of Misuse) Act, 1994 to provide
for the regulation of the use of pre-natal diagnostic techniques for the purpose of
detecting genetic or metabolic disorders or chromosomal abnormalities or certain
congenital malformation or sex linked disorders and for the prevention of the misuse
of such techniques for the purpose of pre-natal sex determination leading to female
foeticide.
The Supreme Court of India in its recent Judgment observed and issued directions to
central and State Governments, Union Territories, Central Supervisory Board and
Appropriate authorities for proper implementation of the Act. In the words of
Supreme Court of India, It is unfortunate that for one reason or the other, the practice
of female infanticide still prevails despite the fact that gentle touch of a daughter and
her voice has soothing effect on the parents. One of the reasons may be the marriage
problems faced by the parents compelled with the dowry demand by the so-called
educated and/or rich persons who are well placed in the society.
The traditional system of female infanticide where by female baby was done away
with after birth by poisoning or letting her choke on husk continues in a different form
by taking advantage of advance medical techniques. Unfortunately, developed
medical science is misused to get rid of a girl child before birth. Knowing fully well
that it is immoral and unethical as well as it may amount to an offence, foetus of a girl
child is aborted by qualified and unqualified doctors or compounders. This has
affected overall sex ratio in various States where female infanticide is prevailing
without any hindrance.
The Supreme Court of India directed the Central Government to create public
awareness against the practice of pre-natal determination of sex and female foeticide
through appropriate advertisements in the print and electronic media by hoardings and
other appropriate means.
Here are some ideas to prevent female infanticide and female foeticide.
-
Free education for women up to college and even post graduate education in
government run institutions (Similar plans are being implemented in many
states in India)
-
Males should stand up to their own moms and dads when they start chirping
about unwanted female children.
-
Create a feminine movement so that women feel a sisterhood towards each
other and stand up for a woman in a neighbouring house rather than turn a
blind eye.
-
Refuse marriage of women into households or be very careful of families that
have only male children or a very high percentage of males.
-
Do not provide any government incentives to families that have only males.
-
Provide extra incentives for families that have more than one girl child. This
will help correct the gender balance in a few years.
-
If you have a female child, educate her and provide her the same opportunities
as a male child. This is the one thing that makes female killing folks look
foolish and dumb.
-
Encourage marriage of males to educated women. Conversely, an educated
female class will be more aware of their rights.
‒ VINEETA SINGHAL
Associate Editor
NISCAIR
e-mail: [email protected]