ASCP CG Certification Practice Exam Questions and Answers
The suggested level for most constitutional specimen is 550, but 400 is the lowest acceptible level
See CAP regulation CYG.42200
32. Placental tissue is submitted for chromosome analysis, to optimize the liklihood of obtaining fetal cells, where should the tech select tissue from?-
: The fetal side of the spcimen (when possible to be identified from the decidua)
33. In a compound light microscope, the aperature stop affects resolution and contrast by:: Changing the angle of the cone of light inside the objective
34. What is the correct nomenclature to describe a hematologic disorder with trisomy 21 in 6 cells and 14 cells that are normal?: 47,XY,+21?c[6]/46,XY[14]
?c -- indicates questioning whether the trisomy is constitutional or not as it was seen in only 6 cells
35. The G-light bands produced by routine GTG banding represent:: The active regions of the chromosome
aka euchromatin -- gene-rich and GC rich DNA, early replicating
36. Which of the following is not assocated with a microdeletion?
1. Prader-Willi
2. DiGeorge
3. Rubinstein-Taybi
4. Langer-Giedion: 3. Rubinstein-Taybi
Associated with an autosomal dominant mutation in the CREB or CREBBP gene(s) Rarely assocated with a deletion in 16p13.3 (12% of cases, not the predominant cause, detected by FISH)
Presents as facial dysmorphism, broad thumbs, broad big toes, and growth and mental retardation
37. The dark bands produced by routune GTG banding represent:: AT-rich regions of the chromosome
aka heterpchromatin, and gene-poor chromatin, late replicating DNA
38. If GTG banded chromosomes appear ghost-like with little visible banding, one should alter banding prep by:: Decreasing trypsin time (chewed out and non-distinct)
39. If 50 out of 200 interphase nuclei have 3 signals in a prenatal aneusomy FISH analysis for chromosome 18, the results are:: Consistent with trisomy 18 or a structural anomaly of chromosome 18
40. If the same hybridization incubator is used for several different probe strategies, the stringency for each probe can be adjusted by:: adjusting the formamide and salt concentrations
41. Optimal (best) banding quality is achieved for each patient sample by banding:: one trial slide per patient to ensure BEST quality
42. In fluorescent microscopy, the exciter and barrier filters used depend on
?: Stain - because the wavelength for emission can vary per type of fluorescent stain used (i.e. DAPI)
43. What is a possible reason a metaphase cannot be located when switching from the 40x lens to the 100x oil lens?: The 100x objective is slightly unscrewed (can occur when cleaning the scope)
44. What is an action a technologist can take to reduce the risk of repetitve motion injuries when doing analysis on a computer?: Supporting the arm that moves the mouse,
Standing and moving around often, and
alternating hands while operating the computer mouse
45. What is the correct modal number for a patient with Turner syndrome with an isochromosome Xq?: 46 -- because the isochromosome replaces the normal X, causing Turner syndrome
46. What should be used on a cultured CVS sample to obtain more slides for analysis?: Trypsin-EDTA -- to remove adherent cells from the flask or coverslip to split into more vessels
EDTA improves tryp's effectiveness (chelating agent)
47. Cyto studies were ordered on a prenatal patient at 12 weeks gestation after an abnormality was detected via ultrasound. 2 of 15 colonies from seperate primary cultures showed an abnormal cell line of 47,XX,+21. The next step would be to ?: Report the result as this is a true mosaic case and suggest:
repeating amniocentesis,
repeating a detailed ultrasound, or
request percutaneous umbilical blood sample (PUBS)
48. After staining, the chromosomes appear to have indistinct bands with lit- tle contrast. The problem is corrected by:: Increasing trypsin exposure (chroms were muddy and dark)
49. When scoring FISH for DiGeorge syndrome, a tech notices the TUPLE1 signal is present, but one of the control ARSA probe signals is missing in every cell. This result suggests ?: The patient has a deletion of the ARSA region
50. CLIA 1988- (Clinical Laboratory Improvement Amendments) stipulates that equipment must be recalibrated ?: Every 6 months (Standard 493.1217)
51. What type of stained chromosome would produce a better computer image?: Lightly stained chromosomes (best contrast and can be digitally edited easier)
52. What is the nomenclature on a patient with down syndrome referred for a hematologic disorder where only trisomy 21 was found?: 47,XY,+21c[20]
53. 24 hours after culture initiation, a single dish from an amniotic fluid turns cloudy. Which cultures should be disposed?: The single cloudy dish only
54. What is used to reduce mycoplasma contamination?: BM cycline
55. CLIA '88 stipulates that equipment must be recalibrated ?: After a major repair to ensure still operational
56. How should caustic and corrosive chemicals be stored?: Both should be stored in a nonflammable cabinet
57. What factors would contribute to ALL cultures failing in a CO2 incuba- tor?: Temperature
CO2 level
Humidity level
58. What is the modal number for a diploid karyotype and an additional CBG
negative marker chromosome?: 46
CBG = c-bands achieved with barium with Giemsa stain
CBG negative referrs to not having a centromere, which is crucial to being included in the modal number, so this extra fragment does not have a centromere and is not counted towards the total
59. What is included when recording the modal number?: Mar - a marker chromosome is included because it has a centromere
60. What is the BEST way to avoid producing ghost-like, pale chromosomes while staining?: Decrease trypsin time
61. In order to ensure successful harvest, each new batch of hypotonic solution should be evaluated .: By comparing new hypotonic solution to that already in use