Inbreeding is mating of closely related animals, especially humans. The result can be disastrous which is why most cultures have rules against it. Christianity is typical in this regard.
Ron Unz has just published an older article called Incest Barriers and Litter Size dealing with this issue. One interesting comment came from Anonymous, that author of many essays; it tells us about The Whitakers, An Incestuous Family In West Virginia. They are definitely losers in the lottery of life; proof, if you need it that Incest is a bad idea.
Then there is Fred, my writer of choice. He is also from West Virginia, from Prince George's County, as distinct from the upscale one in Maryland. Fred explains White Trash and the American Experience; The Whites are a family living in squalor and Boone County. They are deeply sincere Appalachian plebeians. The Wild and Wonderful Whites of West Virginia is the film that exposes them. You might care to get it & see for yourself; that's quite close enough for most of us. Inbred? Is there any other way for the shiftless, idle, irresponsible & to be fair, gormless?
A similar event happened in Australia. It was written up by the Wikipedia as the Colt Clan Incest Case. It all went wrong over a few generations; less than a century. This implies that incest is rare in humans.
The Colts seem to have been cunning & inbred. The Whites were hooligans with some(?) inbreeding. The Whitakers were simply pathetic.
There are problems with deafness caused by inbreeding among small founder populations. Examples are Al-Sayyid Bedouin Sign Language & Deafness on Martha's Vineyard
Inbreeding ex Wiki
Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically.[2] By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and other consequences that may arise from expression of deleterious or recessive traits resulting from incestuous sexual relationships and consanguinity.Inbreeding results in homozygosity, which can increase the chances of offspring being affected by deleterious or recessive traits.[3] This usually leads to at least temporarily decreased biological fitness of a population[4][5] (called inbreeding depression), which is its ability to survive and reproduce. An individual who inherits such deleterious traits is colloquially referred to as inbred. The avoidance of expression of such deleterious recessive alleles caused by inbreeding, via inbreeding avoidance mechanisms, is the main selective reason for outcrossing.[6][7] Crossbreeding between populations also often has positive effects on fitness-related traits,[8] but also sometimes leads to negative effects known as outbreeding depression. However increased homozygosity increases probability of fixing beneficial alleles and also slightly decreases probability of fixing deleterious alleles in population.[9] Inbreeding can result in purging of deleterious alleles from a population through purifying selection.[10][11][12]
Inbreeding is a technique used in selective breeding. For example, in livestock breeding, breeders may use inbreeding when trying to establish a new and desirable trait in the stock and for producing distinct families within a breed, but will need to watch for undesirable characteristics in offspring, which can then be eliminated through further selective breeding or culling. Inbreeding also helps to ascertain the type of gene action affecting a trait. Inbreeding is also used to reveal deleterious recessive alleles, which can then be eliminated through assortative breeding or through culling. In plant breeding, inbred lines are used as stocks for the creation of hybrid lines to make use of the effects of heterosis. Inbreeding in plants also occurs naturally in the form of self-pollination..
Inbreeding can significantly influence gene expression which can prevent inbreeding depression.
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Should you? NO!
Gene ex Wiki
In biology, a gene (from genos [1] (Greek) meaning generation[2] or birth [1] or gender) is a basic unit of heredity and a sequence of nucleotides in DNA or RNA that encodes the synthesis of a gene product, either RNA or protein.[3][4][5]During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gene–environment interactions. Some genetic traits are instantly visible, such as eye color or the number of limbs, and some are not, such as blood type, the risk for specific diseases, or the thousands of basic biochemical processes that constitute life.
Genes can acquire mutations in their sequence, leading to different variants, known as alleles, in the population. These alleles encode slightly different versions of a protein, which cause different phenotypical traits. Usage of the term "having a gene" (e.g., "good genes," "hair color gene") typically refers to containing a different allele of the same, shared gene.[6] Genes evolve due to natural selection / survival of the fittest and genetic drift of the alleles.
The concept of gene continues to be refined as new phenomena are discovered.[7] For example, regulatory regions of a gene can be far removed from its coding regions, and coding regions can be split into several exons. Some viruses store their genome in RNA instead of DNA and some gene products are functional non-coding RNAs. Therefore, a broad, modern working definition of a gene is any discrete locus of heritable, genomic sequence which affect an organism's traits by being expressed as a functional product or by regulation of gene expression.[8][9]
The term gene was introduced by Danish botanist, plant physiologist and geneticist Wilhelm Johannsen in 1909.[10] It is inspired by the ancient Greek: γόνος, gonos, that means offspring and procreation.
Gene Expression ex Wiki
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. These products are often proteins, but in non-protein-coding genes such as transfer RNA (tRNA) and small nuclear RNA (snRNA), the product is a functional non-coding RNA. Gene expression is summarized in the central dogma of molecular biology first formulated by Francis Crick in 1958,[1] further developed in his 1970 article,[2] and expanded by the subsequent discoveries of reverse transcription[3][4][5] and RNA replication.[6]The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and utilized by viruses—to generate the macromolecular machinery for life.
In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, i.e. observable trait. The genetic information stored in DNA represents the genotype, whereas the phenotype results from the "interpretation" of that information. Such phenotypes are often expressed by the synthesis of proteins that control the organism's structure and development, or that act as enzymes catalyzing specific metabolic pathways.
All steps in the gene expression process may be modulated (regulated), including the transcription, RNA splicing, translation, and post-translational modification of a protein. Regulation of gene expression gives control over the timing, location, and amount of a given gene product (protein or ncRNA) present in a cell and can have a profound effect on the cellular structure and function. Regulation of gene expression is the basis for cellular differentiation, development, morphogenesis and the versatility and adaptability of any organism. Gene regulation may therefore serve as a substrate for evolutionary change.
Zygosity ex Wiki
Zygosity (the noun, zygote, is from the Greek zygotos "yoked," from zygon "yoke") is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism.Most eukaryotes/a> have two matching sets of chromosomes; that is, they are diploid. Diploid organisms have the same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in a matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system. If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous, and, if both alleles are missing, it is nullizygous.
The DNA sequence of a gene often varies from one individual to another. Those variations are called alleles. While some genes have only one allele because there is low variation, others have only one allele because deviation from that allele can be harmful or fatal. But most genes have two or more alleles. The frequency of different alleles varies throughout the population. Some genes may have alleles with equal distributions. Often, the different variations in the alleles do not affect the normal functioning of the organism at all. For some genes, one allele may be common, and another allele may be rare. Sometimes, one allele is a disease-causing variation while another allele is healthy.
In diploid organisms, one allele is inherited from the male parent and one from the female parent. Zygosity is a description of whether those two alleles have identical or different DNA sequences. In some cases the term "zygosity" is used in the context of a single chromosome.[1]
Allele ex Wiki
An allele (modern formation from Greek ἄλλος állos, "other")[1][2][3] is one of two, or more, forms of a given gene variant.[4] For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles. Nearly every living human's phenotype for the ABO gene is some combination of just these six alleles.[5][6] An allele is one of two, or more, versions of the same gene at the same place on a chromosome. It can also refer to different sequence variations for several-hundred base-pair or more region of the genome that codes for a protein. Alleles can come in different extremes of size. At the lowest possible size an allele can be a single nucleotide polymorphism (SNP).[7] At the higher end, it can be up to several thousand base-pairs long.[8][9] Most alleles result in little or no observable change in the function of the protein the gene codes for.However, sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation. A notable example of this is Gregor Mendel's discovery that the white and purple flower colors in pea plants were the result of "pure line" traits, that is a single gene with two alleles.
Nearly all multicellular organisms have two sets of chromosomes at some point in their life cycle; that is, they are diploid. In this case, the chromosomes can be paired. Each chromosome in the pair contains the same genes in the same order, and place, along the length of the chromosome. For a given gene, if the two chromosomes contain the same allele, they, and the organism, are homozygous with respect to that gene. If the alleles are different, they, and the organism, are heterozygous with respect to that gene.
The Whitakers, An Incestuous Family In West Virginia
Anonymous[145] • Disclaimer says:
They are clearly victims, to be pitied rather than mocked. Their neighbours in Appalachia know them and care about them. Ditto for the Raleigh County deputies. The neighbours have shotguns, while the deputies have pistols. They may have not killed any intruders yet but they are quite willing to. There is concurring comment from @JackOH
Colt Clan Incest Case ex Wiki
The Colt family incest case concerns an Australian family discovered in 2012 to have been engaging in four generations of incest beginning with a couple known as Tim and June Colt, who emigrated from New Zealand in the 1970s. They all lived on a farm near Boorowa, New South Wales.[1][2] The family members' true identities remain unknown to the public. The name "Colt" is a pseudonym used by New South Wales courts and government agencies, as are all of the family's given names. Official involvement came late & might have been sympathetic. The Australian's article is rather more to the point, telling us that seven of them were in prison pending criminal trial. See Colt incest family Real story behind five generations. An Irish write up in The Journal confirms the point - Australia shocked by extreme case of incest, sex abuse and child neglect. The Wiki links to two more similar families; one in Canada & one in Victoria.
Afghans Are Often Inbred And Genetically Messed Up
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From Molecular Genetics & Genetic Medicine:
The population of Afghanistan has been growing rapidly in this century, which makes cousin marriage more often feasible when there is a cultural prejudice in favor of it.
This can be understood by first imagining a Malthusian country with a stable population where only 2 children in each nuclear family survive to reproduce. That means on average, each individual on average has only two opposite sex first cousins, thus reducing the chances of the extended family managing to make the desired first cousin arrange marriage.
Now imagine a fast growing population with four surviving children per pair of parents. On average, each young individual would have
twofour opposite sex first cousins available to marry, doubling the chances.That’s why cousin marriage increased in some third world countries over the second half of the 20th Century as the number of surviving children went up due to better public health and medicine: they’d always wanted to arrange cousin marriages but it often wasn’t often practical due to a lack of cousins.
My impression is that rates of cousin marriage tend to be falling in the 21st century as birthrates fall and the reduction in infectious disease makes the more subtle deleterious effects of genetic disorders more visible. If a huge fraction of children in your village were dying of, say, river blindness then the idea that some fraction of children are sickly or a little less bright than they could be due to inbreeding seems pretty minor. But now we’ve got ivermectin to cure river blindness and elephantiasis, so it’s time to notice more subtle problems.
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Thus writes Steve Sailer, who strikes me as an intelligent man with decent instincts. He benefits from a hostile write up by the Wikipedia @Steve Sailer, a fact to his credit, rather than vice versa.
Al-Sayyid Bedouin Sign Language ex Wiki
Al-Sayyid Bedouin Sign Language (ABSL) is a village sign language used by about 150 deaf and many hearing members of the al-Sayyid Bedouin tribe in the Negev desert of southern Israel. As deafness is so frequent (4% of the population is deaf, compared to 0.1% in the United States)[2] and deaf and hearing people share a language, deaf people are not stigmatised in this community and marriage between deaf and hearing people is common. There is no separate deaf culture or politics either.
Deafness on Martha's Vineyard
Deafness on Martha’s Vineyard, phenomenon in which a disproportionate percentage of the population living on Martha’s Vineyard, an island off the southeastern coast of Massachusetts, U.S., was affected by a hereditary form of deafness. The overall rate of Vineyard deafness peaked in the 19th century at an estimated 1 in every 155 islanders, which far exceeded the rate of deafness in the American population generally.
Vineyard deafness appeared as complete deafness at birth with no associated anomalies. It was caused by a recessively inherited genetic mutation that was traced to Kent county, England. Emigrants from that region, some of whom came specifically from an area called The Weald, settled on Martha’s Vineyard in the late 17th century. It is thought that a history of genetic relatedness among some parents, combined with intermarriage on the island, contributed to the spread of the genetic defect that caused Vineyard deafness.