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TRISOMY 18 also known as Trisomy E or

Edwards syndrome

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is a geneticdisorder inwhich a personhas a third

copy of geneticmaterial fromchromosome 1

8, instead of the usual twocopies.

http://www.nlm.nih.gov/medlineplus/ency/article/002327.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/002327.htm

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Trisomy 18 is arelatively commonsyndrome. It is threetimes more common ingirls than boys . It is named after John H.

Edwards , who firstdescribed the syndromein 1960. It is the second most

common autosomaltrisomy, after DownSyndrome, that carriesto term

Trisomy 18 is caused bythe presence of three asopposed to two copiesof chromosomes 18 in afetus or infant's cells.

The incidence of thesyndrome is estimated as

one in 3,000 live births .

The incidence increasesas the mother's ageincreases . The syndromehas a very low rate ofsurvival , resulting fromheart abnormalities,kidney malformations,and other internal organdisorders.

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Clenched handsCrossed legs (preferred

position)Feet with a roundedbottom (rocker-bottomfeet)Low birth WeightLow-set earsMental deficiencySmall head ( microcephaly )Small jaw ( micrognathia )UnderdevelopedfingernailsUndescended testisUnusual shaped c hest(pectus carinatum )

http://www.nlm.nih.gov/medlineplus/ency/article/003272.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003306.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003321.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003321.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003321.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003321.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003321.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003306.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003272.htm

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Examination of thepregnant woman mayshow an unusually largeuterus andextra amniotic fluid. Anunusually small placentamay be seen when thebaby is born.

Physical examination of the infant may showunusual fingerprintpatterns. X-rays mayshow a short breastbone. Chromosomes

study show trisomy 18,partial trisomy,or translocation.

3D ULTRASOUND

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Treatment of

children withTrisomy 18 isplanned on a case-by-case basis.

Which treatmentsare used dependson the patient'sindividualcondition.

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50% of infants do not survive beyond the firstweek of life. Some children have survived to the teenageyears, but with serious medical anddevelopmental problems.

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Prenatal diagnosis of trisomy 18 is possiblewith an amniocentesis or chorionic villussampling and chromosome studies onamniotic cells. Parents who have a child withtranslocational Trisomy 18 and wantadditional children should have chromosomestudies, because they are at increased risk of having another child with Trisomy 18.

http://www.nlm.nih.gov/medlineplus/ency/article/003921.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003406.htmhttp://www.nlm.nih.gov/medlineplus/ency/article/003921.htm

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PATAUs SYNDROME also known as

trisomy 13 and trisomy D

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is a chromosomal condition associated with

severe intellectual disability and physicalabnormalities in many parts of the body.Due to the presence of several life-threatening medical problems, many infants

with trisomy 13 die within their first days orweeks of life .Only five percent to 10 percent of childrenwith this condition live past their first year.

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Trisomy 13 was first observedby Thomas Bartholin in 1657,

but the chromosomal nature of the diseasewas ascertained by Dr. Klaus Patau in

1960. The disease is named in his honor.Patau syndrome was also described in Pacificisland tribes.

http://en.wikipedia.org/wiki/Thomas_Bartholinhttp://en.wikipedia.org/wiki/Klaus_Patauhttp://en.wikipedia.org/wiki/Klaus_Patauhttp://en.wikipedia.org/wiki/Klaus_Patauhttp://en.wikipedia.org/wiki/Thomas_Bartholinhttp://en.wikipedia.org/wiki/Thomas_Bartholin

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They have :heart defects,brain or spinal cordabnormalities,very small or poorlydeveloped eyes(microphthalmia),extra fingers and/ortoes,an opening in the lip (acleft lip) with or withoutan opening in the roof of the mouth (a cleftpalate), andweak muscle tone

(hypotonia).

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Trisomy 13 occurs in about 1in 16,000 newborns.Although women of any age

can have a child with trisomy13, the chance of having achild with this conditionincreases as a woman getsolder.

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Most cases of Patau'ssyndr ome re sultfrom trisomy 13, whichmeans each cell in thebody has three copiesof chromosome 13instead of the usualtwo copies.Patau syndrome canalso occur when part of chromosome 13becomes attached toanother chromosome(translocated) beforeor at conception.

http://en.wikipedia.org/wiki/Trisomyhttp://en.wikipedia.org/wiki/Trisomyhttp://en.wikipedia.org/wiki/Trisomy

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Medical management of children with

Trisomy 13 is planned on a case-by-case.Treatment of Patau syndrome focuses on theparticular physical problems with which eachchild is born.Surgery may be necessary to repair heartdefects or cleft lip and cleft palate . Physical,occupational, and speech therapy will helpindividuals with Patau syndrome reach theirfull developmental potential.

http://en.wikipedia.org/wiki/Cleft_liphttp://en.wikipedia.org/wiki/Cleft_palatehttp://en.wikipedia.org/wiki/Cleft_palatehttp://en.wikipedia.org/wiki/Cleft_lip

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More than 80% of children with Patausyndrome die within the first month of life