PPT explains how to interpret a karyotype and any disorder if present

1. PRACTICAL 6
KARYOTYPE/IDEOGRAM ANALYSIS FOR
THE SYNDROMES WITH COMMENTS ON
NUMERICALAND STRUCTURAL
VARIATIONS IN CHROMOSOMES
TYBSc ZOOLOGY SEMESTER VI
PRACTICAL ; 03
DATE ; 25/11/2021
THURSDAY

3. KARYOTYPE ; A SET OF CHROMOSOMES OF INDIVIDUAL SPECIES IS CALLED AS KARYOTYPE
MORPOLOGICAL
CONTRAST BETWEEN
THE CHROMOSOMES
ON THE BASIS OF
1. Chromosome Number
2. Relative length
3. Chromosome set
4. Position of centromere

4. NORMAL HUMAN KARYOTYPE
A; long metacentric
B; long sub-metacentric
C; medium sized sub
metacentric
D; large acrocentric
E; small sub metacentric
F; small metacentric
Small acrocentric
NORMAL HUMAN MALE KARYOTYPE
22 PAIRS OF AUTOSOMES
A PAIR OF SEX
CHROMOSOMES
46 XY

6. NORMAL HUMAN FEMALE KARYOTYPE

7. GROSS MUTATIONS
chromosome number; occurs due to non -disjunction
chromosome structure

8. The number of sets of chromosomes in a cell or an organism. Haploid/diploid
ANEUPLOIDY;
numerical change occur in particular pair of chromosome while rest all pairs are
normal
A. HYPERANEUPLOIDY ; CH NUMBER INCREASE
B. HYPOANEUPLOIDY; CHROMOSOME NUMBER DECREASE
Euploidy
Complete set of chromosome is
extra or deleted.
Not seen in animals
Seen in different species of wheat
Types of aneuploidy

10. SYNDROME CHROMOSO
MAL
ABNORMILI
TY
KARYOT
YPE
/number of
chromosom
es
Discovered by Year
Turner
Syndrome
XO 44+XO (45) Dr.Henry Turner 1938
Klinefelter’s
syndrome
XXY 44+XXY
(47)
Dr. Harry Klinefelter 1942
Patau
syndrome
trisomy 13 47 Dr. Klaus Patau 1960
Edward
syndrome
trisomy 18 47 John Edward
Down’s
syndrome
Trisomy 21 47 Dr. John Langdon down : described 1st.
Dr, Lejeune: identified it as chromosomal condition
Dr. John : 1866
Dr.Lejeune:
1959
Cri-Du-Chat
syndrome
5q arm
deletion
46 Jerome Lejeune 1963
D-G
translocation
(A form of
Robertsonian
Translocation)
Place of 21st
chromosome is
changed and
joines to 15th
chromosome
46 --- ----

11. TURNER SYNDROME; monosomy of sex ch
KARYOTYPE DEPICTING TURNER SYNDROME

12. A. TURNER’S SYNDROME
TOTAL NO. OF CHROMOSOMES =45
• It is an example of chromosomal aneuploidy.
• Monosomy of sex chromosme
• Discovered by Dr. Henry Turner :1938
• Caused when in a female cell one normal x ch and
the other sex ch is missing or structurally altered
• happens due to non-disjunction during formation
of gamates.
• SYMPTOMS :
Female having turner syndrome shows following symptoms
• Stunted growth evident by the age 5
• Underdeveloped ovary: Ova not produced: sterile
female.
• Overies are small: No sex hormones produced: Poorly or
No secondary sexual characters developed
• Webbed neck, prominent folds of skin at the corner of
eyes (Epicanthal folds), Puffy hands and skin.
• Distinctive heart, kidney, liver abnormalities are present

13. PATAU SYNDROME; 13 trisomy
KAROTYPE DEPICTING PATAU SYNDROME

14. B. PATAU’S SYNDROME
TOTAL NUMBER OF CHROMOSME= 47
Dr. Klaus Patau 1960
Trisomy 13 : Hyperploidy
Chromosome 13 is present in 3 copies
Caused by nondiscjunction of ch 13

15. C. EDWARD’S SYNDROME
• Total no. of ch; 47, trisomy 18
• British geneticist John Edward ;1960
• Non-disjunction of ch 18
• At first or second meiotic division in either of the parents
• 3 copies of ch 18 are present
• Hyperaneuploidy
KARYOTYPE DEPICTING EDWARD SYNDROME

16. DOWN’S SYNDROME ; 21 trisomy

17. DOWN’S SYNDROME/MONGOLISM
• Total number of chromosomes ; 47; trisomy 21
• First described by; 1866 ; Dr. John Langdon Down
• 1959; French physician ; jerome Lejeune ;identifies it as chromosomal
condition
• Hyperploidy
SYMPTOMS;
• 4 feet tall; webbed neck
• Round face with epicanthal folded eyes
• Constantly open mouth, malformed ears, flattened nose
• Congential heart defects, hand and feet defects
• Mild to moderate developmental disability, impulsive behavior, short attention
span, poor judgement, slow learning capacity

18. Dr. HARRY KLINEFELTER
TRISOMY OF SEX CHROMOSOME
TOTAL CH ; 47 – 2X AND 1 Y : 47;XXY
NON-DISJUNCTION OF SEX
CHROMOSMES DURING MEIOSIS
EITHER IN MALE OR FEMALE.
SYMPTOMS;
• Male with small testes, produce
less testosterone
• Gynecomastia –breast
enlargement
• Poorly developed secondary
sexual characters , reduced
facial/body hair/infertile
• Underdeveloped genitalia
libs are longer than average

19. KLINEFELTER’S SYNDROME

20. TOTAL NO. OF CH ; 46
5 PARM DELETION
JEROME LEJEUNE 1963
AUTOSOMALABONORMALITY
SHORT ARM OF CHROMOSOME 5 IS DELETED
DELETION OCCURS DURING GAMATE FORMATIONOR IN
EARLY FOETAL DEVELOPEMNT
• SYMPTOMS
• it is associated with characteristiccry resembling
that of kitten, cat like mewing
• microcephaly -small sized head
• eyes widely separated apart
• epicathal folds
• physical and mental retardation

21. D-G TRANSLOCATION
• Form of Robertsonian translocation’
chromosomal aberration due to structural variation
shows translocation between interchromaosomal
pair.
• The long arm of chromosome 21 –G group
breaks at centromere, translocates and joins with
long arm of ch 15 D GROUP
• One of the chromosome of 15th pair appears
longer than the homologus chromosome
• as place of 21st ch is changed and gets
translocated to 15 it is called D-G
TRANSLOCATION
SYMPTOMs
• person appears normal as there is no additon or
deletion of chromosome
high risk of having abnormal children
• Their children ; may be normal or carry fusion
chromosome or they may inherit a missing or
extra long arm of acrocentric chromosome

22. THANK YOU