L29 Flashcards
WHAT is the 3 type of genetic disease?
1-monogenic disease
2-polygenic disease
3-chromosomal disease
monogenic disease happen due to ?
it happen due to mutation occurring in the gene [ one gene] that encode for a protein
polygenic disease happen due to ?
due to mutation in multiple gene and their interaction with environmental factors
example of monogenic disease ?
Sickle-cell anemia [ single gene disorder ]
example of polygenic disease ?
Type 2 diabetes
what cause human syndromes?
human syndromes are caused by chromosomes abnormalities [ numerical abnormality or structual abnormalities ]
what is the 2 type of numerical abnormality ?
1- aneuploidy
2-polyploidy
what is aneuploidy ?
gain [ trisomy 47] or loss [ monosomy 45 ] of chr in a cell and it can occur in both sex chr and autosomes
Ex of disease happen in sex chr ?
turner syndrome in girls [ monosomy 45 chr]
klinefetter syndrome in boys [ trisomy 47 chr]
monosomy [ turner ] and trisomy [ klinefetter ] occur as a result of an error in ?
error in meiosis cell division through Nondisjunction
what is nondisjunction ?
it failure for homogenies chr to separate properly during mieosis
true or false
nondisjunction can occur in meiosis 1 or mitosis?
false !
it can occur in meiosis 1 or meiosis 2
Autosomes can occur through ?
non disjunction in meiosis or mitosis [alternations in autosomes ]
what is the 3 type of trisomies that result in baby that can survive for a time after birth ?
[13,18,21]
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what is trisomy 21 [ down syndrome] symptoms ?
significantly reduced IQ
chracteristic features
what happen during mieosis in trisomy21 [ down syndrome]?
nondisjunction during meiosis 1 [homologous chromosomes pair fail to separate and go to the same doughter cell
nondisjunction during meiosis 2 [ sister chromatids fail to separate and will go to the same gamete
what happen during mitosis in trisomy 21[ down syndrome]?
non disjunction of ch 21 causing one cell to have 47 chr and the other have 45 chr
trisomy 18 cause ?
edwards syndrome, which is a severe disorder of heart and kidneys and if the fetus survive to birth the median lifespan is 5 to 15 days
trisomy 13 cause ?
patau syndrome ,which is sever birth defect including heart and kidney disorder as well as malformation
80% newbabys do not survive long then one year
what is sex chr syndrome and autosomes chr syndrome ?
sex chr [ happen in meiosis
Monosomy [ turner syndrome ]
trisomy [ klinefetter syndrome ]
Autosomes chr [ happen in meiosis and mitosis]
trisomy 21 [ down syndrome ]
trisomy 18 [ eduard syndrome ]
trisomy 13 [ patau syndrome]
true or false
true polyploidy commanly occurring in human although it occurs in some tissues [ especially in the liver ]
false
it rerly occurring in human
diploid male gameteis ferilized by normal haploid female gamates give us ?
triaploid 3n=69 [ baby miscarry or die within the first year of life
male gameteis ferilized by diploid female gamates give us ?
tetraploid 4n=92 [ baby usually dies in uterus
when does structural chr happen?
Structural abnormalities occur whena part of a chromosome is abnormal. Examples:
Deletion
Duplication Insertion Inversion
Translocation
what is delation ?
give me an Ex
A portion of the chromosome is missing or deleted. Best example is Cri du chat syndrome
nm
• Cri du chat syndrome:
• Deletion at the end of short arm of chromosome 5,
focus chr 5 555555555
what is duplication ?
a portion of the chr is duplicated resulting in extra genetic material
protein 22
chr 17
what is insertion ?
portion of one chromosome has been deleted from its normal place and inserted into another chromosome.
what is inversion?
An inversion is a chromosome rearrangement in which a segment of a chromosome is reversed end to end.
• An inversion occurs when a single chromosome undergoes breakage and rearrangement within itself.
- Inversions are of two types:
- Paracentric
- Pericentric =within centromere
what is translocation ?
Reciprocal Translocation is the exchange of chromosome segments between two non-
homologous chromosomes.
Translocation occurring between chromosomes 14 and 21[ down syndrome]
