The condensed mass attached to the nuclear membrane of some female cells are called Barr Body.
Barr Body
All chromosomes are normal in number and shape. Notice the X and the Y chromosomes.
A normal male karyotype
Cri du Chat (5p-) [Cat-cry syndrome]
All chromosomes are normal in number and shape except for the deleted upper segment of 5p in a
female. The baby has a distinctive low pitched cry like mewing of a cat.
Guess what?
Some commonly used nomenclature in karyotype writing
d
Some of the structural chromosomal anomalies
Other structural chromosomal anomalies
Inversion, Deletion and translocation
Duplication
In the balanced translocation, although mislocated, there is net loss or gain of any piece, while in the
unbalanced type, there is a loss of a piece from the genome (proximal segment of chromosome 7).
Comparison between balanced and unbalanced translocation
A. Types of deletion.
B. Interstitial deletion of a piece of long arm on chromosome 1.
Types of Chromosomal Deletion
A
B
Clinical features of retinoblastoma in a child
A pediatric malignancy of the retina, retinoblastoma occurs in hereditary & sporadic forms. Shown is a
patient with a unilaterla tumor (Rt. eye).
A. Gross specimen showing the retinal mass. B. Histopathological section within the tumor.
Retinoblastoma
A huge well defined rounded mass is shown in the lower poly of the kidney, compressing the rest of
renal tissue.
Wilm tumor : Gross
Child with Turner syndrome and low posterior hairline and webbed neck (A) and short fourth
metacarpals (B). Infant with Turner syndrome with lymphedema of the hand (C) and feet (D).
Some clinical features of Turner’s Syndrome
Note in this karyotype, 2 X chromosome in addition to a Y-chromosome.
Karyotype of Classical Klinefelter Syndrome