Karyotype images This PowerPoint file contains a number of images of karyotypes that may be useful for teaching of genetics concepts. You may use these slides and their contents for non-commercial educational purposes. More slides will be added to this series shortly.

The Karyotype: an international description total number of chromosomes, sex chromosome constitution, anomalies/variants. 46,XY 47,XX,+21 47,XXX 69,XXY 45,XX,der(13;14)(q10;q10) 46,XY,t(2;4)(p12;q12) 46,XX,del(5)(p25) 46,XX,dup(2)(p13p22) 46,XY,inv(11)(p15q14) 46,XY,fra(X)(q27.3) 46,XY/47,XXY

The Karyotype: an international description total number of chromosomes, sex chromosome constitution, anomalies/variants. 46,XY 47,XX,+21 Trisomy 21 (Down syndrome) 47,XXX Triple X syndrome 69,XXY Triploidy 45,XX,der(13;14)(p11;q11) Robertsonian translocation 46,XY,t(2;4)(p12;q12) Reciprocal translocation 46,XX,del(5)(p25) Deletion tip of chromosome 5 46,XX,dup(2)(p13p22) Duplication of part of short arm Chr 2 46,XY,inv(11)(p15q14) Pericentric inversion chromosome 11 46,XY,fra(X)(q27.3) Fragile X syndrome 46,XY/47,XXY Mosaicism normal/Klinefelter syndrome

Nomenclature of cytogenetic bands. The ideograms show ideal G-banding patterns at 550 band resolution. Major bands are labelled 1,2,3, etc., going from centromere to telomere. Major band 11q1 (11q means the long arm of chromosome 11, 11p the short arm) is divided into sub-bands 11q11 – 11q14, and at the highest resolution 11q14 splits into 11q14.1 – 11q14.3. Fig. 2.5 ©Scion Publishing Ltd Redrawn from ISCN 2005 with permission from S. Karger AG, Basel.

Fig. 2.9 ©Scion Publishing Ltd

Fig. 2.11 ©Scion Publishing Ltd Karyotype showing trisomy 21 (47,XX,+21) Fig. 2.11 ©Scion Publishing Ltd

Fig. 2.13 ©Scion Publishing Ltd Karyotype of Isabel Ingram. Although Isabel will never be able to have children normally, treatment with estrogens can allow her to develop normal secondary sex characteristics and greatly assist her personal and social life. Modern reproductive technology has allowed some Turner syndrome patients to bear children using donor eggs. Treatment with growth hormone can result in improved growth and final height. Fig. 2.13 ©Scion Publishing Ltd

Fig. 2.14 ©Scion Publishing Ltd G-banded karyotypes of Ellen’s chromosomes. There is a balanced translocation. Chromosomes 1 and 22 have exchanged segments (arrows). The translocation is described as 46,XX,t(1:22)(q25;q13) Fig. 2.14 ©Scion Publishing Ltd

Fig. 2.15 ©Scion Publishing Ltd G-banded karyotype of baby Elizabeth. She has inherited Ellen’s normal chromosome 1 but her translocated chromosome 22 (arrow). She is trisomic for the portion of chromosome 1 distal to 1q25, the translocation breakpoint, and monosomic for chromosome 22 distal to 22q13. Fig. 2.15 ©Scion Publishing Ltd

Fig. 2.16 ©Scion Publishing Ltd How the 1;22 translocation in Ellen Elliot originated. Chromosome 1 and 22 broke at the positions indicated by the arrows, and the cell’s DNA repair machinery rejoined the ends to form the two derivative chromosomes as shown. The derivative chromosomes are labelled der(1) and der(22). Fig. 2.16 ©Scion Publishing Ltd

Fig. 2.20 ©Scion Publishing Ltd A Robertsonian translocation. The inset shows how this common type of chromosome abnormality arises. The short arms of all the acrocentric chromosomes (13, 14, 15, 21, 22) contain similar DNA. Inappropriate recombination between two non-homologous chromosomes produces the fusion chromosome, which functions as a normal single chromosome in mitosis. The small acentric fragment comprising the two distal short arms is lost. Fig. 2.20 ©Scion Publishing Ltd

Fig. 4.14 ©Scion Publishing Ltd 22q11 metaphase FISH. The green spots are a control probe, used to identify the two copies of chromosome 22 and confirm that hybridization has taken place. The red spots are the TUPLE1 probe. Only one of the two copies of chromosome 22 contains the sequence that hybridizes to this probe. Fig. 4.14 ©Scion Publishing Ltd

Fig. 4.15 ©Scion Publishing Ltd Interphase FISH test for trisomy 21. The chromosome 21 probe is labelled with a red fluorochrome and a control probe (for chromosome 18) is labelled in green. The two green dots show that the hybridization has worked for this cell, and the three red dots show that there are three copies of chromosome 21. The clinical report is based on examining a large number of cells. For prenatal diagnosis a mix of differently coloured probes from chromosomes 13, 18, 21, X and Y is often used. Fig. 4.15 ©Scion Publishing Ltd

Fig. 4.16 ©Scion Publishing Ltd Array-CGH result on the patient shown in Figure 4.3. The whole genome was surveyed, but only results for the probes from chromosome 12 are shown. There is a duplication involving 39 contiguous clones from 12q24.1. Fig. 4.16 ©Scion Publishing Ltd

47,XX,+21

47,XX,+13

47,XX,+18

45,X

47,XXY

47,XYY

45,XX,der(14;21)(q10;q10)

46,XX,t(4;15)(q2?1.3;q13)

46,XX,t(9;22)(q34;q11)

ish der(9)(ABL-),der(22)(BCRsp+conABLsp+,ABLsp+,BCRsp+)

46,Y,fra(X)(q27.3)

Fragile X Chromosome

47,XX,+?mar

46,X,r(X)

ins(22;9)(q11;q13q34)

46,XY.ish del(15)(q11.2q11.2)(SNRPN-)

46,XY.ish del(15)(q11.2q11.2)(SNRPN-)

46,XX.ish del(22)(q11.2q11.2)(TUPLE1-)

46,XX.ish del(22)(q11.2q11.2)(TUPLE1-)

46,X,del(X)(p21.1)

46,XX,del(4)(p15.2p16.?2)

ish del(7)(q11.23q11.23)(ELN-) Williams syndrome

three separate copies of chromosome 21 Trisomy 21: 47,XX,+21 three separate copies of chromosome 21

Three copies of all the chromosomes: triploidy

Human chromosome banding patterns seen on light microscopy Different chromosome banding resolutions can resolve bands, sub-bands and sub-sub-bands

FISH - fluorescence in situ hybridisation

Example of FISH

Trisomy 21 amniocyte

Chromosomes seen through a microscope