Acquired characteristic

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For Lamarck's theory of Inheritance of acquired characteristics, see Acquired characteristics.
This article deals primarily with Acquired characteristics by humans. You can improve this article by adding information about Acquired characteristics by plants and non-human animals.

An acquired characteristic is a non-heritable change in a function or structure of a living biotic material caused after birth by disease, injury, accident, deliberate modification, repeated use, disuse, or misuse, or other environmental influences. Acquired traits, which is synonymous with acquired characteristics, are not passed on to offspring through reproduction alone.

The changes that constitute acquired characteristics can have many manifestationsnae and degrees of visibility but they all have one thing in common: they change a facet of a living organisms' function or structure after the organism has left the womb.

  • "Lucky", an adult, three-legged dog who got her name after surviving being hit by a car when she was a pup, just gave birth to five puppies. None had limps, malformed/abnormal legs, or were missing a leg.
  • Bonsai are normal plants that have been grown to remain small through cultivation techniques.

Acquired characteristics can be minor and temporary like bruises, blisters, shaving body hair, and body building. Permanent but inconspicuous or invisible ones are corrective eye surgery and organ transplant or removal. Semi-permanent but inconspicuous or invisible traits are vaccinations and laser hair removal. Perms, tattoos, scars, and amputations are semi-permanent and highly visible.

Applying makeup and nailpolish, dying one's hair or applying henna to the skin, and tooth whitening are not examples of acquired traits. They change the appearance of a facet of an organism, but do not change the structure or functionality.

Inheritance of acquired characters was historically proposed by renowned theorists such as Hippocrates, Aristotle, and French naturalist Jean-Baptiste Lamarck. Conversely, this hypothesis was denounced by other renowned theorists such as Charles Darwin. Today, although Lamarckism is generally discredited, there is still debate on whether some acquired characteristics in organisms are actually inheritable.[1][2]

Disputes[edit]

Acquired characteristics, by definition, are characteristics that are gained by an organism after birth as a result of external influences or its own activities that change its structure or function and cannot be inherited.[3][4][5] Therefore, every condition an organism is born with must be considered an inherited characteristic.

Inherited characteristics, by definition, are characteristics that are gained or predisposed to by an organism as a result of genetic transmission from its parents and will be passed to the organism's offspring.[6][7][8] Therefore, every condition an organism does not gain or develop because of inheritance of its parents' genetic information must be considered an acquired characteristic.

Certain genetic conditions[edit]

It is fairly common for mammalian eyes to change color in the first years of life. This happens, with human infants and kittens being some well-known examples, because the eyes of the baby, just like the rest of its body, are still developing. This change can be as simple as blue to brown, or can involve multiple color changes in which neither the child's parents nor his/her doctors know when the changes will stop and what the final eye color will be.[9]

Changes in eye color signal changes in the arrangement and concentration of pigment in the iris, which is an example of structural color. Even though this change happens after birth, it is strictly as result of genes. While changes in eye appearance (and function, and structure) that occur because of acquired characteristics like injury, illness, old age, or malnutrition are definitely acquired characteristics, the infantile color change as described above is usually considered inherited.

When diseases are caused by environmental influences, such as iodine deficiency or lead poisoning, their resultant symptoms are unequivocally agreed to be acquired characteristics. However, it is debatable whether changes in bodily functions due to disorders that are partly or wholly genetic in origin are actually "acquired".

Wholly genetic disorders, such as Huntingtons, are ticking time-bombs that are inherited from parents' genes and are present before birth but the symptoms that develop, aka are "acquired", after birth are simply delayed manifestations of the inherited trait.

Disorders that are partially genetic, such as ALS and allergies, mean the organism has inherited a predisposition to develop, aka "acquire", a certain condition but that inherited increased likelihood can be reduced or further increased depending on acquired characteristics of the organism.

New mutations, (often somatic, spontaneous and sporadic), not inherited from either parent are called de novo mutations.[10] The consensus on whether certain prenatal spontaneous mutations and genetic disorders that occur as a result of meiotic and chromosome errors[11] or during cell division after conception, like Cystic fibrosis and Down syndrome, are considered to be acquired or inherited[12] is unclear. Mutations and meiotic errors can be considered inherited since the organism is born with them in its genes, but they can also be seen as prenatal acquired characteristics since they are not actually inherited from its parents.[13] With de novo mutations and division errors, the relationship between the offspring's altered genes and gene inheritance from the parents is technically spurious.[13] These genetic errors can affect the mind as well as the body and can result in schizophrenia,[14][15] autism,[11] bi-polar disorder ,[16] and cognitive[17] disabilities.

For more details on mutations and cell division errors, see Cause of Cystic fibrosis, Genetic origins of Down syndrome, Causes of autism, Chromosome abnormality and Mutation.

Prenatal[edit]

The definitions of inherited and acquired characteristics leave a gray area for trauma, pre-existing and gestational maternal conditions that affect the fetus, as well as chemical and pathogen exposures and trauma that happen before and while an organism is born, such as AIDS, syphilis, Hepatitis B, chickenpox, rubella, unregulated gestational diabetes, and fetal alcohol syndrome.[18] Most infections won't affect a fetus if the pregnant mother contracts it, but some can be transmitted to babies via the placenta or during birth, and others cause more severe symptoms in pregnant women or can cause complications to the pregnancy.[19]

For more details on complications of labor and delivery, and health issues in pregnancy, see Category:Pathology of pregnancy, childbirth and the puerperium.

Types[edit]

The World Health Organization defines health as a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity.[20] Acquired characteristics don't need to affect the health of an organism, (a scar, suntan, or perm) but examples that do are often the first that come to mind when thinking of acquired characteristics since they are the easiest to observe and the ones that we, ourselves, are most familiar with.

Physical[edit]

Physical acquired characteristics can stem from various environmental influences such as disease, modification, injury, and regular or infrequent use of body parts.

Mental[edit]

Mental traits are acquired by learning and adapting native traits to the environment of the individual.

Little Albert experiment

trauma trigger

cognitive

character

Behavior

Socialization

Parenting style

Sociological Illness

Sentiments are the result of the compounding of primary emotions, being "bound up with knowledge and ideas."[21] Only through vast experience in the natural world can humans learn to recognize objects in all of the various orientations in which we encounter them on a day-to-day basis.[22] The ability to do something well is an acquired characteristic, since a skill comes from one's knowledge, practice, aptitude, etc.[23]

Mind-body correlation[edit]

Many acquired characteristics, such as injuries and diseases, directly affect only the mind but indirectly affect the body or directly affect only the body but indirectly affect the mind.

Suppose you develop an articulation disorder after being hit in the head with a fastball from a Pro baseball pitcher. Once your concussion wears off, this is your only symptom. There's nothing wrong with your body, and nothing wrong with most of your mind but you stutter and slur and mispronounce your words so that people have a very hard time understanding you.

How would such a condition affect your life if you were a child? A child would be teased mercilessly by peers and have trouble communicating with friends and family.

A student would not be able to communicate easily with classmates (collaborative assignments), teachers, tutors, and certain classes (choir, public speaking).

What if you had a job where you needed to be able to talk to people? You wouldn't be able to easily talk to customers, other employees, or your boss. You couldn't answer phones or make calls, greet customers, do presentations. You couldn't call your pet's name. You wouldn't even be able to use a fast food drive-through or tell your waitress what you wanted to order! You couldn't say, "I love you," to your child, parent, or significant other.

How would you cope with the functional disorder? With the changes and the stress those changes caused?

The example in the above link deals with the loss of a single mental function. Imagine what would happen if a part of your body stopped working. Even something as simple as a broken finger causes many changes in lifestyle to compensate for the difference in function: writing, typing, drawing, driving, hobbies like gardening, fishing, or sports, using video game and TV controls, texting and dialing phone numbers, using cutlery to eat, opening a bag of chips or soda can, preparing food for yourself or your family, playing with your child or pet, unlocking and opening doors, bathing, brushing your teeth and hair, dressing yourself, typing your shoes, and more.

For more details on stress and the relationship between mind and body, see Stress (biology), Stress (physiology), Stress (psychological), Quality of life, Mind-body interventions, and Category:Stress.

The person unable to pronounce words clearly would suffer additional stress, anxiety, frustration, and emotional upset from his functional limitation. There would be anxiety over financial hardships like bills from medical exams and tests, and a possible leave of absence or termination from work. Physical effects of your articulation disorder could be paper cuts from your notepad, headaches over the stress, stubbed toes and sprained ankles from rushing to where you accidentally left you notepad, pulling a muscle from hauling a laptop around, etc. Worry could induce ulcers. If you have to cut back on spending, your (and your family's) nutrition could suffer. There would be less money for fine dining, going out with friends, and indulging in toys and hobbies.

Those close to you - family, friends, lovers - would be negatively affected by your limitation and your relationship with them would suffer as well.

For more details on living with conditions that require special care and life adjustments, see Disease management (health), Chronic care management.

Origin[edit]

There are four main types of disease: pathogenic disease, deficiency disease, hereditary disease, and physiological disease.

Prenatal[edit]

Congenital disorders, known more commonly as birth defects, are DEFINITION.

It is possible for an unborn child to contract fetal diseases and perinatal infections.

Category:Disorders originating in the perinatal period

Trauma[edit]

Suppose a pregnant woman is shot in her abdomen and the bullet hits the fetus, causing a non-fatal injury. Depending on the length of time between injury and birth, the baby could be born either with a still-healing wound or with a fully healed scar. Regardless of its state of healing, the gunshot wound could be considered an inherited characteristic, since the baby is born with the condition, or could be considered an acquired characteristic, since the condition did not happen as a result of genes inherited from its parents.

The gray area is that a prenatal gunshot wound obviously isn't an inherited, genetic condition but it can't be an acquired trait because it didn't happen after the baby's birth.

Chemical exposure[edit]

Hormones are chemicals released by a cell or a gland in one part of the body that affect cells in other parts of the organism.

Chemicals are substances with distinct molecular compositions that are produced by or used in a chemical process.

While all types of asbestos fibers are known to cause serious health hazards in humans,[24][25][26] it is not known whether its toxicity is due to mechanical damage or unwanted signal channels which might disrupt normal cell activity.

Drugs are any substance that, when absorbed into the body of a living organism, alter normal bodily function. Drugs can be legal and be used as is medically prescribed by a doctor or be illegal to buy, sell, possess, and administer. They can be naturally occurring (such as caffeine and cannabis) or man-made (such as Chlorpromazine). Both legal and illegal drugs can be misused and abused. They have varying levels of dependence and some can cause addiction.

Main article: Barratry (common law)
Common commercial: "Women who took drug X during their pregnancy and had babies born with these conditions may be entitled to financial compensation."
For more details on how chemicals and drugs affect can fetal development and post-natal organism function., see Category:Poisoning and certain other consequences of external causes, Category:Teratogens, and Category:Congenital malformation due to exogenous toxicity.

Maternal conditions during gestation[edit]

Worth noting is the importance of prenatal nutrition to proper mental and physical development. pregnancy Category:Health issues in pregnancy

Prenatal nutrition and birth weight

Risk factors in pregnancy

Premature birth

Pregnancy#Concomitant_diseases Maternal health Complications of pregnancy

AIDS

A correlation between fraternal birth order and male sexual orientation has been suggested to be responsible for up to 15 percent of homosexuality.[27] It is hypothesized to have something to do with changes induced in the mother's body when gestating a boy that affects subsequent sons, possibly an in-utero maternal immune response.[28][29][30][31]
For more details on how birth order and gender can affect subsequent fetuses., see Prenatal hormones and sexual orientation.

Thyroid disease in pregnancy Gestational diabetes

Small for gestational age Large for gestational age Failure to thrive

Smoking and pregnancy Health effects of tobacco Complications related to amniotic fluid Maternal physiological changes in pregnancy

Prenatal stress Prenatal memory

Immune tolerance in pregnancy Passive immunity Vertical transmission

Nutrition and pregnancy Vitamin B12 deficiency

Mirror syndrome

Reproductive health

Non-Mendelian inheritance Maternal influence on sex determination

Maternal environment and exposures[edit]

There is also reason to believe that the immune system of a baby will be healthier if, during pregnancy, the mother's immune system was regularly stimulated by exposure to pathogens.

"...A mother's farm exposure affects her baby's T regulatory cells. These cells, it is now believed, act to suppress immune responses and thereby maintain immune system homeostasis to contribute to healthy immune development. ... The babies of mothers exposed to farms have more and better functioning regulatory T cells."

[32]

Postpartum[edit]

Acquired disorder

Season of birth

Childhood[edit]

Main article: Helminthic therapy

It is posited that the absence of exposure to parasites, bacteria, and viruses is playing a significant role in the development of autoimmune diseases in the more sanitized Western industrialized nations.[33][34] Lack of exposure to naturally occurring pathogens may result in an increased incidence of autoimmune diseases.[35][36] (See hygiene hypothesis.)

A complete explanation of how environmental factors play a role in autoimmune diseases has still not been proposed. However epidemiological studies, such as the meta analysis by Leonardi-Bee, et al.,[35] have helped to establish the link between parasitic infestation and autoimmune disease development, in other words, exposure to parasites reduces incidence of an autoimmune disease developing.

"Early life exposure to microbes (i.e., germs) is an important determinant of adulthood sensitivity to allergic and autoimmune diseases such as hay fever, asthma and inflammatory bowel disease."[37]

"Immunological diseases, such as eczema and asthma, are on the increase in westernized society and represent a major challenge for 21st century medicine. ...[G]rowing up on a farm directly affects the regulation of the immune system and causes a reduction in the immunological responses to food proteins,"[38] which not only means less severe reactions to food allergies, lactose intolerance, gluten sensitivity, etc., but reductions in the likelihood of developing them in the first place.

Developmental impact of child neglect in early childhood

Sexuoerotic tragedy

Disease[edit]

Disease is a broad term that refers to any condition that impairs the normal physical or mental (or both) function of an organism. (Though this definition includes injuries, it will not be discussed here). Diseases can arise from infection, environmental conditions, accidents, and inherited diseases.

It is not always easy to classify the source of a health problem. For instance, people can develop gout, which is known to cause permanent or near permanent changes to the human body,[39] because of diet, inherited genetic predisposition, as a secondary condition from other diseases, or as an unintended side effect of certain medications.

Infectious diseases can be caused by pathogens and microorganisms such as viruses, prions, bacteria, parasites, and fungi.

Further information: Transmission (medicine) and Natural reservoir

For infectious, environmental, and genetically predisposed conditions, lifestyle choices such as exercise, nutrition, stress level, hygiene, home and work environments, use or abuse of legal and illegal drugs, and access to healthcare (including an individual's financial ability and personal willingness to seek medical attention) especially in the early stages of an illness all combine to determine a person's risk factors for developing a disease or condition.

Precancerous condition Progressive disease localized disease to spread to other area of the body.

Diet[edit]

The World Food Program and UNICEF reported last year that chronic malnutrition had left 42 percent of North Korean children stunted — meaning their growth was seriously impaired, most likely permanently. An earlier report by the U.N. agencies warned that there was strong evidence that physical stunting could be accompanied by intellectual impairment.

—Demick, Barbara. 2-14-2004. The Seattle Times.[40]

"North Koreans are on average three inches shorter than their cousins in the South."

This statistic, or versions of it, have been quoted for some time. In 2010, the late Christopher Hitchens put the difference at six inches in an article in Slate, titled "A Nation of Racist Dwarfs". Martin Bloem is head of nutrition at the World Food Programme, which has been providing food aid to North Korea since 1995. He says poor diet in the early years of life leads to stunted growth. "Food and what happens in the first two years of life is actually critical for people's height later," he says.

Today, according to the World Food Programme, "one in every three children [in North Korea] remains chronically malnourished or 'stunted', meaning they are too short for their age".
—Knight, Richard. 4-22-2012. BBC News[41]

Outline of nutrition

cougar with shortened legs at Big Cat Rescue

Poor nutrition and frequent injury and disease can reduce the individual's adult stature, but the best environment cannot cause growth to a greater stature than is determined by heredity.

Vitamin K deficiency malnutrition Nutrition disorder

Sleep debt

Injury[edit]

Trauma is "a body wound or shock produced by sudden physical injury, as from violence or accident,"[42] or, more simply put, is "a physical wound or injury, such as a fracture or blow."[43]

Accidental injuries, most of which can be predicted and thus prevented, are the unintentional negative outcomes of unforeseen or unplanned events or circumstances which may have been avoided or prevented if reasonable measures had been taken or if the risks involving the circumstances leading up to the accident been recognized and acted upon (minimized).

Battery is a criminal offense involving the use of force against another that results in harmful or offensive contact.[44] (Assault is fear/belief of impending battery.) Violence is defined by the WHO as the intentional use of physical force or power, threatened or actual, against oneself or others that either results in or has a high likelihood of resulting in injury, death, psychological harm, maldevelopment or deprivation.[45] Consent

Head trauma[edit]

Head trauma in the form of a traumatic brain injury, stroke, drug or alcohol abuse, and infection have been known in some cases to cause changes to a person's mental processes, the most common being amnesia, ability to deal with stress and changes in aggression. There have also been documented cases of a person's personality changing more drastically, the best-known case being Phineas Gage, who in 1848 who survived a 1.1 meter long tamping iron being driven through his skull (though almost all presentations of Gage's subsequent personality changes are grossly exaggerated).

There is also the rare condition called Foreign Accent Syndrome in which someone who has suffered a brain injury will appear to speak in a new language or dialect. This is typically thought to be due to an injury to the linguistic center of the brain causing speech impairment that just happens to sound like a persons non-native language. This is thought to be the reasoning behind the urban legend where someone wakes from a coma or surgery and suddenly speaks a new language.[46]

Body modification[edit]

Body modification is the deliberate altering of the human body for any non-medical reason, such as aesthetics, sexual enhancement, a rite of passage, religious reasons, to display group membership or affiliation, to create body art, shock value, or self-expression.[47]

The frequency of occurrence depends on the location, extent, and number of modifications, and, perhaps most importantly, on the mind of each individual being asked to accept the modifications on another.

The change can be extreme but still be accepted or at least tolerated by the majority (cosmetic surgery), or be extreme and opposed by most people (neck rings). Ear piercing is a minor aesthetic alteration that is widely accepted (on females' ears). The acceptance of highly diverse tattoos and body piercings depends on location, size, and number and, perhaps most importantly, on the mind of each individual being asked to accept it.

Also known as maiming, mutilation is any form of physical injury aimed at degrading the bodily appearance or function of a living organism's body. Examples, include amputation, foot binding, and genital cutting. The reasons for these changes can be rite of passage,

Like other acquired characteristics, body modification results in permanent physiological changes that cannot be passed on to offspring genetically alone.

Use and disuse of body parts[edit]

Constant physical exercise such as swimming, running, and weight lifting can cause muscles to develop. However, muscles and other body parts can also waste away through atrophy due to disuse of said body parts. Both of these phenomena occur most of the time due to the living style of the organism and their effects on the physiology of the organism constitute of acquired characteristics such as either stronger muscles or disintegrated tissue.

Many repetitive activities (sports, manual labor, chewing) create wear patterns and leave impressions on the bones and fascia that are highly specialized (sometimes even unique) to the activity. Over a lifetime, even such simple activities as posture and gait leave telltale impressions on our bodies. shoes.

Category:Occupational diseases Occupational disease hobbies, sports

Other[edit]

Pregnancy, drug consumption, exposure to chemicals, and other environmental influences can cause acquired characteristics to occur.

Complications of pregnancy Wilson's disease

See also[edit]

References[edit]

  1. ^ "The Inheritance of Acquired Characteristics". Am J Public Health (N Y) 15 (6): 549. June 1925. doi:10.2105/ajph.15.6.549-a. PMC 1320859. 
  2. ^ Nisbet-Brown, E.; Wegmann, T. G. (1981). "Is acquired immunological tolerance genetically transmissible?". Proceedings of the National Academy of Sciences of the United States of America 78 (9): 5826–5828. doi:10.1073/pnas.78.9.5826. PMC 348875. PMID 7029546.  edit
  3. ^ http://www.thefreedictionary.com/acquired+characteristic The Free Dictionary: Acquired characteristic
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  5. ^ http://medical-dictionary.thefreedictionary.com/Acquired+characteristics The Free Dictionary:Acquired characteristic
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  13. ^ a b http://www.sciencedaily.com/releases/2007/07/070724113757.htm "New Model For Autism Suggests Women Carry The Disorder And Explains Age As A Risk Factor". "Spontaneous mutations are changes in a chromosome that alter genes. Germ-line mutations are newly acquired in a germ cell of a parent, and sometimes are transmitted to offspring at conception. ... “The fact that germ-line mutations increase with age places older parents at a higher risk of having children with autism...” said CSHL co-author of the study [Dr.] Michael Wigler. ... Wigler suggests that “what we now know about spontaneous mutations and autism offers an alternative to traditional thinking about genetic disorders as purely heritable from a parent." "ScienceDaily." (July 24, 2007). Accessed May 17, 2012.
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  15. ^ http://www.sciencedaily.com/releases/2008/05/080530132220.htm "Gene Mutations Responsible For 10 Percent Of Schizophrenia Pinpointed". "People with schizophrenia from families with no history of the illness were found to harbor eight times more spontaneous mutations..." "ScienceDaily". (May 30, 2008). Accessed May 17, 2012.
  16. ^ http://www.sciencedaily.com/releases/2011/12/111221140347.htm "Rare Genetic Mutations Linked to Bipolar Disorder". "Scientists report that abnormal sequences of DNA known as rare copy number variants, or CNVs, appear to play a significant role in the risk for early onset bipolar disorder." "ScienceDaily". (Dec. 21, 2011). Accessed May 17, 2012.
  17. ^ http://www.sciencedaily.com/releases/2011/04/110418114005.htm "Intellectual Disability Is Frequently Caused by Non-Hereditary Genetic Problems, Study Finds". "Mutations in a group of genes associated with brain activity frequently cause intellectual disability, according to a new..." "ScienceDaily". (Apr. 18, 2011). Accessed May 17, 2012.
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  26. ^ Collegium Razmzzini 2010 Statement on Asbestos
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  32. ^ [1] "Farm Moms May Help Children Beat Allergies". "Mothers exposed to farms, particularly to barns and farm milk, while pregnant confer protection from allergies on their newborns, according to a group of German researchers, who will present their findings at the American Thoracic Society's 2008 International Conference in Toronto on May 21." ScienceDaily. (May 20, 2008). Accessed May 17, 2012.
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  37. ^ http://www.sciencedaily.com/releases/2012/03/120322142157.htm "Getting the Dirt On Immunity: Scientists Show Evidence for Hygiene Hypothesis". "Previous human studies have suggested that early life exposure to microbes (i.e., germs) is an important determinant of adulthood sensitivity to allergic and autoimmune diseases such as hay fever, asthma and inflammatory bowel disease." ScienceDaily. (Mar. 22, 2012). Accessed May 17, 2012.
  38. ^ http://www.sciencedaily.com/releases/2012/02/120208132549.htm "Growing Up On a Farm Directly Affects Regulation of the Immune System, Study Finds". "Immunological diseases, such as eczema and asthma, are on the increase in westernised society and represent a major challenge for 21st century medicine. A new study has shown, for the first time, that growing up on a farm directly affects the regulation of the immune system and causes a reduction in the immunological responses to food proteins." ScienceDaily. (Feb. 8, 2012). Accessed May 17, 2012.
  39. ^ http://www.nlm.nih.gov/medlineplus/ency/article/000353.htm
  40. ^ "Effects of famine: Short stature evident in North Korean generation". Accessed May 17, 2012.
  41. ^ Are North Koreans really three inches shorter than South Koreans? Accessed May 17, 2012.
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  44. ^ Black's Law Dictionary Garner, p. 162
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  46. ^ http://www.npr.org/blogs/health/2011/06/01/136824428/a-curious-case-of-foreign-accent-syndrome
  47. ^ What is body modification?

External links[edit]