Genetics doubt

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Genetics doubt

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Doc2378
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01/25/06 - 12:16 PM

Can someone please explain

Adjacent I segregation versus Adjacent II segregation versus Alternate segregation???? rolling eyes

Also, whats the difference between recombination within a paracentric inversion versus recombination within a pericentric inversion? rolling eyes

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reet
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01/25/06 - 01:04 PM

these are ROBERTSONIAN TRANSLOCATIONS.. --translocations occur in ACROCENTRIC chromosomes. and involve LOSS of short arms and subsequent fusion of long arms.

ALTERNATE SEGREGATION is--- (balanced) - short arms dont contain essential genetic material.. so will be normal CARRIERS..(NOT CLINICALLY AFFECTED).

ADJACENT translocation-- unbalanced--- LONG ARM missing.. effect will be TRISOMY,,MONOSOMY.

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reet
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01/25/06 - 01:10 PM

INVERSION --LIKEchromosome broken at two points ,,,,very small segement is inverted

.pericentric inversions--involve CENTROMERE.

Paracentric inversion---dont INVOLVE centromere.

THESE inversions still has retained their genetic material--so they are CARRIERS(UNAFFAECTED )...but offsprings will be having... DELETIONS.

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Doc2378
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01/25/06 - 02:06 PM

Thanks Reet...very helpful. Appreciate it!

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reet
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01/25/06 - 11:44 PM

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Andrew000
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01/30/06 - 10:04 AM

Adjecent segregation-1..centromeric region of non homologus chromosomes segregates;

Adjecent segregation-2.centromeric region of homologus chromosomessegregates.

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