Term
| 2 main types of translocations / 2 types of each of those |
|
Definition
| reciprocal and robertsonian; balanced or unbalanced |
|
|
Term
| balanced reciprocal translocation denotation |
|
Definition
|
|
Term
| t/f balanced chromosomal translocations are typically phenotypically normal |
|
Definition
|
|
Term
| unbalanced chromosomal translocations typically result in (3) |
|
Definition
| mental retardation, and/or congenital abnormalities in the fetus, or early pregnancy loss |
|
|
Term
| children of balanced translocation parents are usually |
|
Definition
| unbalanced translocations |
|
|
Term
| "derivative of chromosome 8" (2) |
|
Definition
| mostly chrom 8 with some of the translocated chromosome on it; does not know which chromosome to align with during meiosis, resulting in 3 possible pairings, two of which are nonviable (viable gametes are viable because they contain all the genetic material) |
|
|
Term
|
Definition
| euploid gametes, half w/ normal chromosomes and half with both translocated chromosomes |
|
|
Term
|
Definition
| aneuploid gametes which die. each gamete gets one normal chromosome and one translocation chromosome with duplications and deletions |
|
|
Term
| how often do alternate segregations occur instead of adjacent segregations? |
|
Definition
| occur in about equal frequency |
|
|
Term
|
Definition
| chromosome with equal arms |
|
|
Term
|
Definition
| centromere just off-center |
|
|
Term
|
Definition
| centromere is near an end |
|
|
Term
| robertsonian translocation |
|
Definition
| when the long arms of 2 acrocentric chromosomes fuse at the centromere, with loss or partial loss of short arms |
|
|
Term
| t/f the short arm regions of acrocentric chromosomes carry essential genes |
|
Definition
| false; robertsonian translocations result in normal phenotypes |
|
|
Term
|
Definition
|
|
Term
| most common robertsonian translocation denotation |
|
Definition
|
|
Term
| robertsonian translocations result in _ conceptions |
|
Definition
| trisomic; example, 14;21 -> trisomy 21 |
|
|
Term
| a mother with a rob. trans. w/ chrom 21 has a _% chance of having a baby with translocation Downs / father risk |
|
Definition
| 10-15. risk is <1% for fathers who are rob. carriers |
|
|
Term
| risk for recurrence of trisomy 21 when a couple has a baby with translocation downs in which the translocation ocurred de novo in an egg or sperm before fertilization |
|
Definition
|
|
Term
| chromosome trisomies that usually miscarry in the first trimester |
|
Definition
| 14,15 or 22, so rob. trans. carrier = higher miscarriage risk |
|
|
Term
|
Definition
| errors in chromosomal crossover during meiosis - chromosomal translocations - breaking without rejoining - crossover within a chromosomal inversion |
|
|
Term
|
Definition
| loss of half of normal activity of a protein causes disease - microdeletion related |
|
|
Term
| which deletions are usually fatal |
|
Definition
|
|
Term
|
Definition
| congenital heart defect, assymetric face, low calcium level |
|
|
Term
| segmental aneuploidy / may be due to (2) |
|
Definition
| = duplications / unequal crossing over, crossing over within an inversion loop |
|
|
Term
| charcot marie tooth disease |
|
Definition
| peripheral meuropathy, slow progressive weakness and atrophy of muscles. due to dup(17) -> myelin gene duplicated |
|
|
Term
|
Definition
| breakage and union within the same arm |
|
|
Term
|
Definition
| breakage and reunion on either side of the centromere |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| which kind of inversion results in nonviable gametes? (dicentric/acentric) |
|
Definition
|
|
Term
| which kind of inversion results in higher risk for abnormal pregnancy, dups and dels? |
|
Definition
|
|
Term
| chromosomal abnormalities in cancer (4) |
|
Definition
| translocations, deletions, duplications,, inversions |
|
|
