303:) is one of the most prevalent chromosomal abnormalities amongst live births. Of all trisomy 21 pregnancies, approximately 80% end in spontaneous abortions or still-births. 1–5% of people diagnosed with having Down Syndrome are actually in fact "high-grade" trisomy 21 mosaics. The rest of trisomy 21 mosaics are marked as "low-grade" mosaics, meaning the chromosomal mutation occurs in less than 3–5% of respective tissue. While high-grade trisomy 21 mosaics, demonstrate similar features to full Down Syndrome, low-grade mosaics have a tendency to show milder features; however, the effects are quite variable depending on the distribution of the trisomic cells.
245:
66:
186:– Chemical compounds that are sufficiently similar in structure and chemistry to the nitrogenous bases of DNA, such that they are able to be incorporated in the sequence. These analogs do not have the same pairing properties of normal bases, therefore they can pair incorrectly with nucleotides during replication.
42:. Mutations that occur after the zygote has formed can be caused by a variety of sources that fall under two classes: spontaneous mutations and induced mutations. How detrimental a mutation is to an organism is dependent on what the mutation is, where it occurred in the genome and when it occurred.
290:
is the most common human postzygotic mutation. It is highly associated with age, being detectable in at least 10% of blood cells for 14% and 57% of males around 70 and 94 years of age, respectively. Men with LOY have a higher all-cause mortality and cancer mortality compared with unaffected males.
675:
Forsberg, Lars A.; Halvardson, Jonatan; Rychlicka-Buniowska, Edyta; Danielsson, Marcus; Moghadam, Behrooz Torabi; Mattisson, Jonas; Rasi, Chiara; Davies, Hanna; Lind, Lars; Giedraitis, Vilmantas; Lannfelt, Lars (January 2019). "Mosaic loss of chromosome Y in leukocytes matters".
327:. These mutations are able to be transmitted to the offspring and give rise to a constitutional mutation. Constitutional mutations is a mutation that when present in one cell, is also present in all other cells associated with the organism.
90:, the affected double stranded DNA will produce one doubled-stranded daughter containing the missing purine, resulting in an unchanged sequence. The other strand will produce a shorter strand, missing the purine and its complementary base.
174:– Causes pyrimidine (T or C) nucleotide bases on the same strand to covalent join forming a pyrimidine dimer. Thymine-thymine dimers are the most common mutation caused by UV light. Since dimers cause a disruptive kink in DNA structure,
56:
Postzygotic changes to a genome can be caused by small mutations that affect a single base pair, or large mutations that affect entire chromosomes and are divided into two classes, spontaneous mutations and induced mutations.
311:
Somatic mutations are the result of a change in the genetic structure after fertilization. This type of mutation also involves cells outside of the reproductive group and thus is not transmitted to future descendants.
291:
Additionally, LOY is associated with greater risk for
Alzheimer's disease and cardiovascular disease. Smoking increases the risk of inducing LOY more than three times and has a dose-dependent effect on LOY-status.
236:
A large determinant of the severity of consequences caused by postzygotic mutations is when and where they occur. As a result, consequences can range from being negligible to incredibly detrimental.
784:
Haitjema, Saskia; Kofink, Daniel; Setten, Jessica van; Laan, Sander W. van der; Schoneveld, Arjan H.; Eales, James; Tomaszewski, Maciej; Jager, Saskia C. A. de; Pasterkamp, Gerard (2017-08-01).
344:
Acuna-Hidalgo, Rocio; Bo, Tan; Kwint, Michael P.; van de Vorst, Maartje; Pinelli, Michele; Veltman, Joris A.; Hoischen, Alexander; Vissers, Lisenka E. L. M.; Gilissen, Christian (2015-07-02).
73:
Most spontaneous mutations are the result of naturally occurring lesions to DNA and errors during DNA replication without direct exposure to an agent. A few common spontaneous mutations are:
227:– Compounds that attach an alkyl group to the four bases. When an alkyl group is added to guanine, it can lead to the incorrect pairing with thymine and disrupt the accuracy of replication.
727:
Forsberg, Lars A; Rasi, Chiara; Malmqvist, Niklas; Davies, Hanna; Pasupulati, Saichand; Pakalapati, Geeta; Sandgren, Johanna; StĂĄhl, Teresita Diaz de; Zaghlool, Ammar (June 2014).
833:
Dumanski, Jan P.; Rasi, Chiara; Lönn, Mikael; Davies, Hanna; Ingelsson, Martin; Giedraitis, Vilmantas; Lannfelt, Lars; Magnusson, Patrik K. E.; Lindgren, Cecilia M. (2015-01-02).
248:
Mosaicism arises after the zygote has formed and a mutation occurs during development. The mutated cell line can be passed down to offspring if the germ cells are affected.
130:– The hydrogen atom on a nucleotide base is repositioned causing altered hydrogen bonding pattern and incorrect base pairing during replication. For example, the
190:(5-BU) is a common analog to thymine, however the enol form of 5-BU is still able to bind with adenine. The ionized form, on the other hand, pairs with guanine.
162:
often demonstrate mutational specificity, meaning they cause predictable changes in the DNA sequence. A few common mutagens that induce mutations are:
203:– Chemical compounds that place themselves between stacked nitrogenous bases in DNA, causing a frameshift mutation. Some intercalating agents, like
260:
to be normal while the other cell line(s) to be abnormal. As a result, the individual is considered to be a mosaic of normal and abnormal cells.
900:"Germinal and Somatic Trisomy 21 Mosaicism: How Common is it, What are the Implications for Individual Carriers and How Does it Come About?"
219:) – Highly reactive oxygen-containing molecules that are capable causing DNA strand breaks and many damaging effects to cellular components.
1008:
252:
When an individual has inherited an abnormality it is usually present in all of their cells. However some mutations like DNA code change,
86:
site. An apurinic site, also known as an AP site, is the location in a genetic sequence that does not contain a purine base. During
786:"Loss of y Chromosome in Blood is Associated with Major Cardiovascular Events During Follow-Up in Men After Carotid Endarterectomy"
424:
Alberts, Bruce; Johnson, Alexander; Lewis, Julian; Raff, Martin; Roberts, Keith; Walter, Peter (2002-01-01). "DNA Repair".
983:
Griffiths, Anthony JF; Miller, Jeffrey H.; Suzuki, David T.; Lewontin, Richard C.; Gelbart, William M. (2000-01-01).
476:
Griffiths, Anthony JF; Miller, Jeffrey H.; Suzuki, David T.; Lewontin, Richard C.; Gelbart, William M. (2000-01-01).
402:
Griffiths, Anthony JF; Miller, Jeffrey H.; Suzuki, David T.; Lewontin, Richard C.; Gelbart, William M. (2000-01-01).
620:"Loss of chromosome Y (LOY) in blood cells is associated with increased risk for disease and mortality in aging men"
567:
Youssoufian, Hagop; Pyeritz, Reed E. (2002-10-01). "Mechanisms and consequences of somatic mosaicism in humans".
729:"Mosaic loss of chromosome Y in peripheral blood is associated with shorter survival and higher risk of cancer"
207:, are capable of blocking replication and transcription, making them incredibly toxic to proliferating cells.
141:
tautomer of thymine can bind with guanine. This results in an incorrect base pair match. Similarly there are
256:
alterations and chromosomal abnormalities, can occur later in development. This would result in one progeny
194:
283:
198:
131:
513:
211:
508:
149:
tautomers of cytosine and adenine that can cause incorrect base pairing with other nucleotides.
69:
Depurination mutation results in one normal strand and one shortened strand after replication.
31:
that is acquired during its lifespan, instead of being inherited from its parent(s) through
846:
8:
346:"Post-zygotic Point Mutations Are an Underrecognized Source of De Novo Genomic Variation"
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which is the fusion of two zygotes, causing a new single zygote with two genotypes.
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Cooke, Marcus S.; Evans, Mark D.; Dizdaroglu, Miral; Lunec, Joseph (2003-07-01).
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Hultén, Maj A.; Jonasson, Jon; Nordgren, Ann; Iwarsson, Erik (2010-09-01).
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Induced mutations are any lesions in DNA caused by an agent or mutagen.
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often have trouble reading the region, slowing down DNA replication.
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is the occurrence of two or more cell lines with different
138:
497:"Oxidative DNA damage: mechanisms, mutation, and disease"
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which can result in incorrect DNA replication and repair.
835:"Smoking is associated with mosaic loss of chromosome Y"
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are the result of a change in the genetic structure of
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137:
of thymine normally pairs with adenine, however the
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270:within a single individual. It is different from
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82:– The loss of a purine (A or G) base to form an
16:Mutation acquired during an organism's lifespan
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1009:Modification of genetic information
989:An Introduction to Genetic Analysis
956:"Somatic mutation – Glossary Entry"
482:An Introduction to Genetic Analysis
408:An Introduction to Genetic Analysis
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985:"Somatic versus germinal mutation"
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430:(4th ed.). Garland Science.
102:group on a base is changed to a
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27:) is a change in an organism's
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618:Forsberg, Lars A. (May 2017).
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427:Molecular Biology of the Cell
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442:"Documents – All Documents"
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362:10.1016/j.ajhg.2015.05.008
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690:10.1038/s41588-018-0267-9
636:10.1007/s00439-017-1799-2
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569:Nature Reviews. Genetics
960:Genetics Home Reference
859:10.1126/science.1262092
404:"Spontaneous mutations"
212:Reactive oxygen species
106:group. This results in
249:
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524:10.1096/fj.02-0752rev
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61:Spontaneous mutations
25:post-zygotic mutation
295:Trisomy 21 mosaicism
284:loss of chromosome Y
278:Loss of chromosome Y
21:postzygotic mutation
851:2015Sci...347...81D
478:"Induced mutations"
321:Germ-line mutations
316:Germ-line mutations
446:faculty.ksu.edu.sa
250:
71:
507:(10): 1195–1214.
501:The FASEB Journal
307:Somatic mutations
224:Alkylating agents
154:Induced mutations
118:being changed to
110:being changed to
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176:polymerases
168:Ultraviolet
95:Deamination
88:replication
52:Mutagenesis
1003:Categories
966:2015-11-14
684:(1): 4–7.
451:2015-12-02
331:References
325:germ cells
254:epigenetic
172:light (UV)
924:1389-2029
867:0036-8075
812:1942-325X
753:1546-1718
698:1546-1718
644:0340-6717
589:1471-0056
533:0892-6638
509:CiteSeerX
286:(LOY) in
272:chimerism
268:genotypes
264:Mosaicism
258:cell line
240:Mosaicism
1014:Mutation
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820:28768751
771:24777449
714:53093907
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597:12360233
541:12832285
380:26054435
160:Mutagens
135:tautomer
108:cytosine
84:apurinic
933:3018721
876:4356728
847:Bibcode
839:Science
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143:amino
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