III. Basic Nomenclature Rules If a structural aberration has occurred in one mem
ID: 211928 • Letter: I
Question
III. Basic Nomenclature Rules If a structural aberration has occurred in one member of a chromosome pair, in may be identified by a mismatch with the homologous banded chromosome. Chromosomes may deviate rom their normal state in many ways. As many ways as one can imagine that a chromosomes structure might be altered is how chromosomes have, in fact, been tound to be abhorm following are common types of structural aberrations. etion: an aberration in which a segment of a chromosome is missing: this may he an aberrat segment large enough to be detected under the microscope (macrodeletion) or so small detected at only sophisticated methods can detect it (microdeletion). Duplication: an aberration in which a segment of a chromosome is repeated and thus is present in more than one copy within the chromosome Rearrangement: an aberration in which a segment of a chromosome is shifted within the same chromosome, sometimes turned upside-down (inversion) Translocation: an aberration in which a chromosome segment is transferred to another chromosome. Variations in the structure of chromosomes are designated by a set of abbreviations adopted by cytogeneticists. The designations for types of aberrations include, but are not limited to: Gain Loss Centromere Deletion cen del der LI ins inv mat at Derivative chromosome (messed up in multiple ways) Duplication Insertion Inversion Maternal Paternal Robertsonian translocation (a translocation resulting from the fusion of 2 centromeres, one long arm is contributed by each of the chromosomes making up th translocation) Translocation Telomere rob tel ter Terminal y Between the locations of x and y detailed information on cytogenetics conventions can be found at lh wisc edu(cvtogenetics/abnormalities/
Explanation / Answer
Q.1. - del(4) (q15) - Deletion in chromosome # 4, long arm(q) at region 1, band 5.
Q.2. - inv(3) (q22q26) - Inversion in chromosome # 3, in the long arm(q) between region 2, band 2 and region 2, band 6.
Q.3. - Option D. Translocation of long arm chromosome # 21 to the short arm of chromosome # 14 ( With deletion ).