Intra family marriages

“I have come here to save our religion…it is better we remain few but pure…” says Mr. Khojeste Mistry as quoted by the Parsiana magazine while speaking against marriage outside the Parsee religion. Oh yes indeed, that’s all very hunky-dory theoretically speaking, but let’s look at this a little practically, shall we? Let’s just sit down and analyze at what cost we’re preserving such a ‘pure’ race. What kind of children will the Parsee community comprise of and what kind of lives are we giving these children. With a meager figure of 75,000 Parsis, intra family marriages, or inbreeding, are taking place on a remarkably large scale. And its consequences are taking a very harsh toll on the children.

Inbreeding is breeding within close family members or extended family members. ‘Extended family’ may include an aunt, uncle, nephew, niece, cousin, or anyone from the same family tree. If practiced repeatedly, it typically leads to a reduction in genetic diversity. Inbreeding often leads to reduced health and fitness (called consanguinity depression).

An inbred individual is likely to possess several physical and health defects, in addition to higher incidence of inheriting a poor trait. They include:
· reduced fertility both in litter size and in sperm viability
· increased congenital defects
· fluctuating facial asymmetry
· lower birth rate
· mental retardation
· higher neo-natal mortality
· attention disorder
· slower growth rate
· smaller adult size
· loss of immune system function, and
· dyslexia.

Twenty-four states have laws forbidding first cousins from marrying, and seven states have limits like requiring genetic counseling. But no countries in Europe have such prohibitions, and in parts of the Middle East, Africa and Asia, marriages between cousins are considered preferable. In some parts of the world, 20 to 60 percent of all marriages are between close biological relatives.

Mammals, most other animals, and higher plants as well, have evolved mechanisms to avoid inbreeding of any sort. Some, like sweet cherries, have even evolved elaborate biochemical mechanisms to ensure that their flowers can not be fertilized by themselves or by very genetically similar individuals. Most pack animals (like lions, primates, and dogs) kick young males out of the pack so as to prevent them from mating with female relatives.

Scientists believe that inbreeding (reproduction between individuals so closely related genetically) leads to an increase in homozygocity, i.e, the same allele at the same locus on both members of a chromosome pair. This occurs because close relatives are more likely to share more alleles than non-related individuals. If an individual has an allele linked to a congenital birth-defect, it is likely that close relatives also have this allele; a homozygote would express the congenital birth defect. Thus, the frequency of a defect-carrying gene in a population may go up when inbreeding occurs.

Thus, in small populations this dynamic would lead to an initial increase in birth defects. It is also likely, but not necessary, that such children would not reproduce. Recent research on the mechanisms of human adaptive immunity suggests that there is a strong evolutionary pressure to maintain as diverse an array ofantibody genes as possible. Despite high hopes, there are no medications that directly increase the activity of the immune system.

Said with simplicity, if one member of a family suffers from a defect, the chances that another member from the same family (immediate or otherwise) is suffering from the same defect are high. Two closely related individuals are likely to have very similar genomes, and if one individual has a gene for a given negative trait, then the other is likely to have it as well. Thus the children from such two individuals would have an unusually high chance of suffering from the same defect. This, as opposed to the theory that the person from outside the family would neutralize the chances of the defected member from passing it on since the outsider does not suffer from the same defect.

Therefore, first cousins are somewhat more likely than unrelated parents to have a child with a serious birth defect, mental retardation or genetic disease. Relatives could both be carriers of the recessive gene that causes cystic fibrosis, for example, but not have any symptoms. A child who gets the recessive gene from both parents is more likely to get the disease.
Where a species is threatened by extinction, the population may fall below a minimum whereby the forced interbreeding between the remaining individuals will result in extinction as at this stage majority of the remaining individuals are from the same family tree and consequently have the same genes (good and bad).

Examples of people who practice consanguinity and belong to a certain ethnic or religious group include the Amish, Mennonites of North America, some African tribes, the Parsees and Druze minorities of Southwest Asia. Dr. K. Bharucha, an eminent pediatrician seconds the argument, “Inbreeding tends to be more prominent in small communities but are not subjected to class or economic status.” The Saudis, the Africans, the Khojas, the Parsees, the Boris, along with plenty of Greek and Roman mythology and Royalty are quite famous in research studies conducted on this particular subject. Ironically enough, these are also the places where a new mutated defect known as the G6PD (Glucose 6-phosphate dehydrogenase) deficiency is prominent. This particular deficiency has no cure.

Historians believe that the Parsis came to India somewhere around the ninth century A.D. The census figures for 1881 indicate that Parsis as a community in India numbered only 85,397. “They brought their women folk and inbreeding continued in India with the same religious zest that made them leave their motherland, to protect their religion.” As written by the eminent pathologist, Dr. P.K. Antia, in his paper, ‘Parsis and Blood Diseases’ published in the Diamond Jubilee Volume of the B.D. Petit Parsi General Hospital. “Zoroastrians breeding amongst themselves, settled in their new home. This natural selection without hybridization has increased certain genetic traits manifested by proclivity to certain disease patterns. Interbreeding and mixing with other races would have led to dilution of these traits.” I think that would ideally explain the increase in the jungliness of the ‘Jungly Iruns’ and the finickiness of the ‘finicky Bawas’. But Dr Bharucha does feel that intermarriage between the two would be the perfect solution to our current dilemma. Cheers! To new and improved jungly Bawas and finicky Iruns!