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Perhaps page 200-202 from the Vojnosanitetski Pregled may be interesting for many of theinformation scientists. Please, comment it.
VOJNOSANITETSKI PREGLED Vojnosanit Pregl 2015; 72(2): 200–202.
Correspondence to: Rajko Igic , Department of Anesthesiology and Pain Management John Stroger Hospital of Cook County, Chicago,
USA. E-mail: igicrajko at gmail.com
PERSONAL OPI NI ON UDC: 314.5:392.543
Quo vadis homine? Or where the marriage goes?
Quo vadis homine? Ili: Kuda ide brak?
Department of Anesthesiology and Pain Management John Stroger Hospital of Cook
County, Chicago, USA, and Department of Clinical Pharmacology, Medical Faculty,
University of Banja Luka, Banja Luka, Republic of Srpska, Bosnia and Herzegovina
Individuals are consanguineous if they are descended
from a common ancestor no more remote than a great, great
grandparent. The progeny of consanguineous parents are re-
garded as inbred. Within a particular society, the population
structure and social customs determine the frequency of con-
sanguineous mating; certain marriage requirements as set
forth by the church and/or state, are designed to prevent very
Inbreeding of domestic animals can preserve and fix
desirable properties and eliminate unfavorable characteristics
from livestock. Closely related animals may be mated to
produce pure breeds of animals and select offspring of spe-
cific desirable types. However, because homozygote is less
fit than heterozygote, inbreeding over a long period risks the
loss of vigor in the offspring. Similarly, plants are inbred for
improved characteristics, either by self-pollination or cross-
ing with closely related plants.
The situation in humans is far more complex. Genetic
effects of inbreeding can be detected in the inbreed individ-
ual, in the form of gene doubling. Affected genes appear as a
single line in each of the common ancestors but double in the
progeny. In other words, modern genetic technology allows
us to show how consanguinity reveals recessive inheritance
and recessive traits.
One means of reducing the accumulation of undesirable
or potentially dangerous genetic material in human popula-
tion is to prevent conception. Same sex marriage, legalized
in some countries, does not produce children and is thus ex-
empt from consanguinity restrictions. If same sex marriage
became universally legal, mating among close cousins, or
even brothers or sisters, uncle and nephew, and aunt and
nice. A same sex marriage without the possibility of concep-
tion is the most efficient way to control reproduction, but this
idea is not universally accepted. In the first place, only a
small percentage of the population would likely be affected,
since the heterosexual population is much larger than a ho-
mosexual one. Secondly, and more importantly, many people
consider a homosexual relationship to be an unnatural, even
evil. It thus becomes increasingly difficult to predict in
which direction marriage will go.
MARRIAGE AT SQUARE ONE
Each nation or state has its own requirements for what
constitutes a valid marriage. These marriage laws form a
contract that allows two persons to live together as husband
and wife. Most marriage laws apply some restrictions, in-
cluding a statement that cousins or closer relatives may not
marry among themselves.
Every society considers incest as a taboo. An accumu-
lation of recessive traits, including morality, in the progeny
of consanguineous mate undermines and weakens society
and can impose long lasting social and medical problems. In
almost all societies mating between parent and offspring,
brother and sister, and among first cousins is considered to
be incestuous, and steps were often taken to prevent it. For
example, The Dušan’s Code (1349) required priests to de-
termine if bride and groom were closely related, and mar-
riages between persons more closely related than fourth
cousins were prohibited (Figure 1). According to the Byzan-
tine customs of the time, a widowed daughter-in-law was
considered by her father-in-law to be his own blood kin.
Families of three or four generations of South Slavs (“zad-
ruga”) lived together under similar marriage and sexual re-
strictions, and punishment for breaking the rules was se-
Nowadays, unions between parent and child or brother
and sister, where 50% of the genome is shared, frequently re-
sult in abnormal offspring. As a result, these incestuous un-
ions are considered illegal in most societies. An exception is
that marriages between uncle and niece or aunt and nephew
may be permitted in Southern India 2 and some isolated lo-
cations. The closeness of this particular relationship is de-
termined by Napoleonic Code (NC) III to have an Inbreeding
Coefficient F (IC) 1/8. The inbreeding coefficient F presents
the probability that an individual receives two identical genes
at the same locus.
Marriages between cousins are the most common types
of consanguineous mating. They are covered as follow: First
cousin marriage (NC IV, IC 1/16), second cousin marriage
(NC VI, IC 1/64); and third cousin marriage (NC VIII, IC
1/256). In some societies marriage between cousins was ac-
ceptable, as in the Nineteenth Century England when Charles
Darwin married his first cousin, Emma Wedgwood 3. Among
first cousin unions, where 1 : 8 genes are shared, the risk of
abnormal offspring is 3–5%, as compared to a risk of about
2% for a non-consanguineous union 4. For marriages be-
tween less closely related cousins, the risks seem little if any
increased over those for the non-consanguineous population.
There is little reason to discourage marriages between less
closely related couples, unless they belong to highly inbreed
groups where heterozygosis for deleterious genes is often
greatly increased. Restrictions of third and fourth cousin
marriage appear to be based mainly on social and moral
Full siblings have both parents in common, and half
siblings share only one parent. Marriages of first cousin and
first half cousins belong to NC VI and IC 1/32, and those
between second cousin and second half cousin belong to NC
VII and IC 1/128. In the Middle East today first cousin mar-
riage occurs at a frequency of around 11 to 68%. Due to spe-
cific social, traditional and religious factors, consanguinity in
Saudi Arabia is very high, with first cousin marriages at ap-
proximately 30 percent 5. Overall consanguinity in a human
population is expressed by an inbreeding coefficient ( =
p1Fi; pi is the relative frequency of inbred individuals with
inbreeding coefficient Fi) 6. The highest inbreeding coeffi-
cient is 0.032 in the Andra-Pradesh (India), due to preferen-
tial uncle-niece mating. High values of inbreeding coeffi-
cients also occur in some other isolated populations, but not
in Polar Eskimos, where a careful avoidance of inbreeding
keeps this value low (< 0.003). For uncle-niece, aunt-
nephew, first cousins, second cousins marriages in human
populations round the globe (from Argentina and the USA to
France, Italy, and India and Japan) the average inbreeding
coefficient is generally about 0.001 or 1 per 1000 6. Marriage
in the USA and in many other countries, is prohibited “be-
tween an ancestor and or descendant; or between a brother
and a sister; between an uncle and a niece; or between an
aunt and a nephew, whether the relationship is through half
or whole blood or adoption” 7.
MARRIAGE AT SQUARE TWO
In most civilized countries, consanguinity is the main,
but not the only reason for the restrictions against marriage
between close relatives. Social, moral, and religious factors
influence an acceptable degree of consanguinity in many
parts of the world.
In contrast to the heterosexual marriage of man and a
woman, same sex marriage does not produce children, thus
eliminating the dangers of inbreeding. Same sex marriage
could become legal among close cousins, brothers, sisters,
uncle-nephew, and aunt-nice provided that the social, moral,
and religious restraints would permit. If Marcus Tallius
Cicero were alive, he would certainly shout: O tempora! O
Despite current technologies for birth control, the total
population of the Earth continues to increase. From time to
time, man and nature reduce population growth through wars
and various disasters, but such measures are insufficient.
Wars, famine, and infective or parasitic diseases that spread
among poor and uneducated people are disastrous means of
controlling the population explosion.
Perhaps marriage without the possibility of conception,
e.g., same sex marriage, could be an additional way to con-
trol reproduction. Indeed, some global strategists might push
for the existing Marriage Laws to be changed accordingly.
The question remains as to how well such a solution would
be accepted. As of today, many individuals still consider
homosexual unions as unnatural. It is thus unclear where this
trend in marriage may go.
Rather than seek such a limited solution to our bur-
geoning population problem, we should better make efforts
towards global peace, spread education to every human be-
ing, reduce inequality, and provide social and economic jus-
tice. Let us again read Dante Alighieri 8, the greatest poet of
the Middle Ages, who suggests in Il Convivio (The Banquet)
that the greatest danger to mankind comes from avarice.
Wealth is not equally distributed, and the craving for it is the
greatest danger to humanity. He believed he had the solution
to avoiding war, but his idea unfortunately did not influence
the rulers who prefer to solve problems militarily. We do
hope that before long strong and creative persons will come
up with a modern formula to find the best way for solution of
rapidly increasing population problem—the sooner the bet-
No potential conflict of interest was reported.
Fig. 1 – Mating at the level of the third cousins. According The
Dušan’s Code, consanguinous matings were considered
between uncle and nice, aunt and nephew, first cousins, second
cousins, and third cousins, including «full» and «half» siblings
in the chain of descent. Full siblings have both parents in
common; half siblings have one parent in common.
= male, = female, = an individual of either sex.
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7. Available from: www.vdh.state.va.us/vital_records/marry.htm
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Received on December 3, 2014.
Accepted on December 4, 2014
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