Flashcards
Th2L03 Chromosomal abnormalities
Cards in this deck (27)
- 1Chromosomal abnormalities are responsible for ___% of spontaneous abortions; most of which are _______50; trisomies
- 2Why are trisomy 13, 18 and 21 the only autosomal trisomies to be bornSmall chromosomes, so fewer genes in triplicate
- 3What is Trisomy 13 calledPatau syndrome
- 4What is the life expectancy of trisomy 13<1year ca. 103 days
- 5What are the common abnormalities associated with Patau syndromeheart defects, incomplete brain development, small or missing eyes, spinal defects, seizures
- 6What is Trisomy 18 calledEdwards syndrome
- 7What are the common abnormalities associated with Edwards syndromeheart defects, heat defects, intestine protruding outside body, kidney malformations
- 8What is the life expectancy of trisomy 1818 - 95% die in utero
50% live to 2 months
5-10% will survive first year of life - 9What is the other name for Trisomy 21Down Syndrome
- 10What serious disease/illness is associated with Trisomy 21acute leukaemia
- 11At birth, babies with Down syndrome usually have certain characteristic signs, including:flat facial features.
small head and ears.
short neck.
bulging tongue.
eyes that slant upward.
oddly shaped ears.
poor muscle tone.
- 12What is the Simian crease○ This crease can be present of no consequence (1 in 30)
○ More likely in down syndrome
- 13What is the cytogenetic nomenclature of Down Syndrome47, XX or XY
- 14What is the life expectancy for Down syndrome50's (around 80%)
- 15What is euploidyThe correct number of chromosomes
- 16What is aneploidyincorrect number of chromosomes
- 17Aneploidy causes:Failure of homologous chromosomes to separate during meiosis I
- 18What errors happen during meiosis I to cause aneploidynon-disjunction errors during oogenesis
some cases of non-disjunction during spermatogenesis - 19What is the cytogenetic nomenclature of Klinefelter syndrome47, XXY
- 20What are the key features of Klinefelter syndrome• Can appear normal
• Diagnosis usually made in late during adult life at the investigation of infertility
• Limited development of secondary sex characteristics
• Genetically male
- 21What is the cytogenetic nomenclature of Turner Syndrome45, X
- 22What is Turner's the only living example ofmonosomy
- 23What are the diagnostic features of Turner's syndrmoe• Diagnosis sometimes made late during adulthood at the investigation of short stature or lack of period (amenorrhoea); no adolescent growth spurt; ova denerate in utero; limited development of secondary sexual characteristics
- 24What is XYY syndrome• Asymptomatic;
• Increased growth velocity
Above average height
- 25What is XX male syndromePhenotypically male but infertile
- 26How is an XX Male possibleResults from unequal combination of sex chromosomes resulting in a small tip of the Y being added on to the tip of the X
This region of the Y bears the SRY (sex determining region of the Y) encoding the testis determining factor... initiates male sex determinations - 27What is the likelihood of an XX male1 in 20K male births
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- Medicine Y1 (Theme 2 | Genetics) Flashcards on Th2L03 Chromosomal abnormalities , created by Emma Allde on 22/08/2016.
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- Emma Allde · Aug 2016
- Updated
- Aug 27, 2016
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