TURNERS SYNDROME. Mike Chan Alex Sproul Casey Sully 11/24/08

Transcription

1 TURNERS SYNDROME Mike Chan Alex Sproul Casey Sully 11/24/08

2 Turner s Syndrome A female is missing part or all of an X chromosome.

3 Turner s Syndrome It is a chromosomal disorder affecting females in which all or part of one of the X chromosomes is absence; monosomy X is most common. Named after an Oklahoma Endocrinologist, Henry Turner, who discovered the disorder in out of 2500 girls are affected.

4 Karyotype 45, X monosomy 45: total number of chromosomes Half or all of chromosome 23 is missing X sex chromosome (female)

5 Symptoms/ Signs Dwarfism (Left) Lymphedema (Above)

6 Symptoms/ Signs Webbing of the neck (Right) Horseshoe Kidney (Below)

7 Sign/Symptoms Short stature Lymphedema (swelling) of the hands and feet Broad chest (shield chest) and widely-spaced nipples Low hairline Low-set ears Reproductive sterility Rudimentary ovaries gonadal streak (underdeveloped gonadal structures) Amenorrhea, or the absence of a menstrual period Increased weight, obesity Shield shaped thorax of heart Shortened metacarpal IV (of hand) Small fingernails Characteristic facial features Webbing of the neck (webbed neck) Coarctation of the aorta Poor breast development Horseshoe kidney Visual impairments sclera, cornea, Glaucoma, etc. Ear infections and hearing loss.

8 Prenatal Screening May be diagnosed by amniocentesis during pregnancy (invasive) Identified with an ultrasound (i.e. heart defect, kidney abnormality, cystic hygroma, and ascites) Karyotype will identify individuals with Turner s Syndrome

9 Possible Medical Treatments *None of the following actually cure Turner s Syndrome Growth Hormones either alone or or w/ low doses of androgen (will increase height of females). Estrogen Replacement therapy (promotes development of secondary sexual characteristics and is essential for bone and tissue maintenance)

10 What Megan May Look Like Physical Traits of Parents Parent 1: Parent 2: Black Hair (BBGG): BB 2 Dominant Alleles For Black Hair GG 2 Dominant Alleles NOT Blonde Hair Widows peak (Ww): 2 Dominant Alleles for a Widows peak Black Hair (BBGG): BB 2 Dominant Alleles For Black Hair GG 2 Dominant Alleles NOT Blonde Hair Widows peak (ww): 2 Dominant Alleles for a widows peak

11 Punnett Squares BG BG W w BG BBGG (Black Hair) BBGG (Black Hair) Ww (Widows Peak) ww (No Peak) w G BBGG BBGG Ww ww BG (Black Hair) (Black Hair) (Widows Peak) (No Peak) w G 4/4 100% Black Haired Offspring 2/4 50% Widows Peak Offspring

12 Megan has black hair and brown eyes Megan has a: webbed neck lower set ears higher hair line swollen hands tiny 4 th metacarpal

13 What to expect Cardiovascular: Females are more prone to circulatory diseases (i.e. congenital heart disease). Pregnancy: Women who want to reproduce need heavy surgeries before being capable of bearing a child. Pregnant mothers with Turner s Syndrome are at risk to cardiovascular complications. Diabetes: Children w/ Turner s Syndrome are more likely to be born with type 1 diabetes, while they they are even more likely to develop type 2 adult onset diabetes. Skeletal: Females w/ Turner s syndrome have an average height of 4 7 and tinier 4 th metacarpals, and maybe the 5 th as well. They are also more likely to develop osteoporosis due to inadequate supply of estrogen and oxygen.

14 Links drome#symptoms /media/1206/ /large.jpg nbioogy/finished%20images/gen20a.gi f