(F) Clinical Cytogenetics (transes-based) Flashcards
(106 cards)
Cytogenetic abnormalities may be found in all of these except:
A. Physiological healthy individuals
B. Normal genetic inheritance
C. Diagnosed genetic disorders
D. Individuals with phenotypic anomalies
B
T or F. Diagnosis of cytogenetic disorders may be made at any stage of life.
T
Diagnosis of cyto disorders are made before birth or in the womb of the mother.
Prenatal cytogenetics
Diagnosis of cyto disorders are made when the baby is born.
Postnatal cytogenetics
Diagnosis of cyto disorders are made during their developmental stage of life.
Childhood and adult cytogenetics
established if the same set of features are seen in several unrelated individuals; assumed to
have a common basis of specific chromosomal abnormalities but may occur in different degrees
syndrome
T or F. Syndromes are usually multifactorial, it is not commonly caused by a common/single-specific chromosomal
abnormality.
F
T or F. Syndromes may be mild, moderate or have severe manifestation.
T
Prenatal Cytogenetics TOF
50%-60% of spontaneous abortions during the early months of pregnancy have a demonstrable chromosomal abnormality
T
Prenatal Cytogenetics TOF
80% of which are autosomal trisomies
F (52)
Prenatal Cytogenetics TOF
1:3 conceptuses (embryo in the uterus) have chromosomal abnormality but seen only in 6:1000 live births due to biological elimination of recognized errors
T
even tho 1 out of 3, most of them are dropped hence 6:1000 and if u do the math 327 are dead for every 1000 ata
Rate of biological elimination TOF
45, X has the lowest rate of elimination
F (95%; Turner’s syndrome)
Rate of biological elimination TOF
90% of Trisomy 13
T (Patau Syndrome)
an extra copy of chromosome 13; characterized by cleft lip, cleft palate, cerebral defects, anophthalmia, simian creases, polydactyly, trigger thumbs, and capillary hemangiomata
Rate of biological elimination TOF
80% of Trisomy 18
T (Edwards Syndrome)
most babies with Edwards’ syndrome will die before or shortly after being born because it causes physical growth delays during fetal development
Rate of biological elimination TOF
90% of trisomy 21
F (65%; down syndrome)
T or F. as the number of chromosomes
goes higher the chances of being born alive is greater
T
Trisomy 21 has a lower biological elimination than Trisomy 13
TOF. as the number of chromosome goes lower, the larger the size of the chromosome and vice versa
T
TOF. the degree of biological elimination is directly proportional to the chromosome number while the degree of survival is inversely proportional.
F (opposite)
the degree of biological elimination is INDIRECTLY proportional to the chromosome number while the degree of survival is DIRECTLY proportional.
T or F. 15% of recognized pregnancies end in DELIBERATE fetal loss
F (sponty)
TOF. THIRD TRIMESTER is the time when
you have the highest number of spontaneous fetal loss
F (80% during first)
most common trisomy seen in abortus
Trisomy 16
TOF. Direct correlation between advanced PATERNAL age (>35 y/o) and incidence of chromosomal abnormalities, the most common being Down’s syndrome
F (Maternal malamang)
Performed on cells obtained by? Get sample from the placenta
On chorionic villus biopsy
Performed on cells obtained by? Get blood sample from a cord that joins the baby to the placenta
On umbilical cord blood