http://images.google.com/imgres?imgurl=http://cmgm.stanford.edu/biochem201/Slides/Chromatin%2520Structure/15%2520EM%2520of%2520Chromatin%2520Solenoid.JPG&imgrefurl=http://cmgm.stanford.edu/biochem201/Slides/Chromatin%2520Structure/&h=738&w=496&sz=160&tbnid=5v_1MWb3-tIJ:&tbnh=138&tbnw=93&start=5&prev=/images%3Fq%3Dchromatin%2Bpicture%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN

http://images.google.com/imgres?imgurl=http://www.people.virginia.edu/~zs9q/zsfig/chromatin1.jpg&imgrefurl=http://www.people.virginia.edu/~zs9q/zsfig/chromatin.html&h=600&w=600&sz=77&tbnid=KQ3b5wmq68sJ:&tbnh=133&tbnw=133&start=9&prev=/images%3Fq%3Dchromatin%2Bpicture%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN

Chromatin: Nucleosomes & Spacer DNA

Normal male karyotype at the 650 band level.

p

q

11.3

11.2

11.1

11.2

12

21

22

23

11.3211.31

11.22

11.21

11.1

11.23

11.2

12.1

12.312.2

21.121.2

21.31 21.3221.3322.122.222.3

23

Chromosome Nomenclature

Chromosome Painting:SKY: Spectral Karyotyping

FISH: Williams SyndromeFluorescent in situ hybridization

Down’s Syndrome

http://www.bbc.co.uk/southyorkshire/myspace/dsa/index.shtml

http://www.sptimes.com/2002/05/12/TampaBay/Lifelong_devotion.shtml

Erik Nichols and mother,St. Petersburg, FL

Erik Nichols, 21, and his sister, 17-year-old Lindsey,on their graduation from high school.

(Saint Petersburg, FL)

http://www.sptimes.com/News/052701/Northoftampa/Sharing_a_triumph_.shtml

http://www.dsne.homestead.com/NewParentsInfo.html

James Webster and mother, Anne

http://www.genecrc.org/site/lc/lc2e.htm

Trisomy 21 Karyotype

Turner’s Syndrome

•Short Stature (mean height < 5 feet)•Failure to develop secondary sex characteristics•Maldeveloped Ovaries (infertility; high risk of ovarian cancer)•Variety of medical problems: cardiovascular, kidney, pancreas,

skeletal, thyroid: MARKED VARIABLE EXPRESSIVITY•Minor physical anomalies: webbed neck, low set ears, puffy hands

and feet: MARKED VARIABLE EXPRESSIVITY

Described in 1938 by Henry TurnerCause isolated in 1960 (loss of one/part of one sex chromosome)

•Normal intelligence•Normal personality (problems of self-esteem and body image that

may be associated with physical anomalies)•Lowered spatial-visualization and quantitative reasoning•? Higher stereotypical feminine interests

Background:

Physical Symptoms:

Behavioral Symptoms:

Turner’s Syndrome

Turner’s Syndrome Karyotype

http://www.genecrc.org/site/lc/lc2e.htm

http://www.xyy.nl/XYYMale.gif

XYY Karyotype

Chromosomal Microdeletions:

Prader-Willi and Angelman Syndromes

PaternalDNA

MaternalDNA

Deleted

Prader-WilliSyndrome

Deleted

AngelmanSyndrome

Gene imprinted (turned off)

Gene not imprinted (turned on)

http://www.ncbi.nlm.nih.gov/books/bv.fcgi?tool=bookshelf&call=bv.View..ShowSection&searchterm=prader&rid=gnd.section.182

http://www.mgm.ufl.edu/faculty/DDriscoll.htm

•Usually caused by micro deletion in region q11-13 of the paternallytransmitted chromosome 15.

•Several genes in this region are genomically imprinted in the maternalchromosome.

•Hence, if there is a paternal deletion in this region, there are no active genes.

•Short stature•Mental retardation, learning difficulties•Decreased muscle tone•Hypogonadism•Emotional lability•Unregulated appetite or hyperphagia ( obesity)

Cause:

Symptoms:

Prader-Willi Syndrome

http://www.bmb.psu.edu/faculty/simpson/lab/07impri/pws.jpg

Prader Willi Syndrome

http://www.bmb.psu.edu/faculty/simpson/lab/07impri/pws.jpg

Tanis, a girl with PWS

•Normal development until 6-12 months, then delayed development•Disproportionate head growth microcephaly•Abnormal EEG, seizures•Marked deficit in language (no words to a few words) but better

communication using nonvebral methods (e.g., facial expressions)•Motoric problems (balance problems, ataxia of gait, hypermotoric actions)•Attention problems (short attention span)•Emotional exuberance (frequent laughter, smiling)

Symptoms:

Angelman Syndrome

Cause:Microdeletion of region q11-13 of chromosome 15 that deletes agene(s) that is paternally imprinted.

http://asclepius.com/angel/phopag.html

AngelmanSyndrome

http://asclepius.com/angel/phopag2.html

Angelman Syndrome