Genetic Hormonal Deficiencies- 28

Question 1

What ways do mutations in coding DNA regions affect proteins

Answer 1

Point mutations- Silent, Nonsense, Missense

Question 2

What other factors can cause diseases

Answer 2

Environmental and genetic factors

Question 3

What is a congenital disorder

Answer 3

A disorder that is present at birth.

Question 4

What are symptoms of congenital hypothyroidism.

Answer 4

Symptoms in infants can be mild, such as low body temperature, poor muscle tone, excessive sleeping

Question 5

What can happen if congenital hypothyroidism is left untreated

Answer 5

It can lead to reduced growth and intellectual dysfunction which is permanent.

Question 6

What is the causes of congenital hypothyroidism

Answer 6

In certain countries, most common cause is maternal iodine deficiencies

Can also be an underdeveloped thyroid gland which is caused by mutations in: Thyroglobulin gene or gene encoding TSH (thyroid stimulating hormone)

Question 7

What is the treatment for congenital hypothyroidism.

Answer 7

Thyroxine (T4) is given orally for treatment daily.

Question 8

How are newborns screened for congenital hypothyroidism.

Answer 8

Involves a “blood spot” procedure where blood is taken and measured for levels of T4 and TSH

Question 9

What causes Allan-Herndon Dudley Syndrome

Answer 9

A loss of function mutation in the MCT8 gene (x-linked)

Question 10

What are the symptoms of Allan-Herndon Dudley Syndrome

Answer 10

Sever cognitive deficiency
Infantile Hypotonia
Progressive spastic Quadripalgeia

Most affected males never walk or sit independantly

Most never speak

Question 11

What are the levels of thyroid hormone in Allan-Herndon Dudley Syndrome

Answer 11

T3 increased
T4 decreased
TSH normal/slightly increased

Question 12

What is the treatment for Allan-Herndon Dudley Syndrome

Answer 12

Diiodothyropropionic Acid (DITPA)

Question 13

What causes Isolated Hormone Deficiency

Answer 13

Most are idiopathic although mutations have been identified in,

GH1 gene encoding growth hormone
GHRHR

Question 14

What is the treatment for Isolated Growth Hormone Deficiency

Answer 14

If treated early children can reach full height

Treatment involves daily injections of GH

Question 15

What are the two parts of the adrenal gland

Answer 15

The cortex and the medulla

Question 16

What does the adrenal cortex secrete

Answer 16

Steroid hormones- Alsosterone, cortisol, adrenal androgens

Question 17

What happens during the short term stress response

Answer 17

Glycogen converted to glucose
Increase blood glucose, blood pressure, breathing rate, metabolic rate

Question 18

What happens in the long term stress response

Answer 18

Sodium ions and water by kidneys
Increase blood volume and blood pressure

Conversion of proteins and fats to glucose
Immune system supressed

Question 19

What causes congenital adrenal hyperplasia

Answer 19

An autosomal recessive disorder caused by a deficiency of enzymes used to make cortisol and aldosetrone

A mutation in the 21-hydroxylase gene

Question 20

What does congenital adrenal hyperplasia cause an increase in

Answer 20

Produces more androgens causing innapropriate or early development of male characteristics

Question 21

What are the symptoms of classical salt wasting 21-hydroxylase deficiency

Answer 21

Ambiguous female genitalia
Reduced aldosterone and cortisol secretion
Increased testosterone

Question 22

What are the symptoms of classical simple virilising 21-hydroxylase deficiency

Answer 22

Ambiguous female genetilia
Normal Aldosterone
Reduced Cortisol
Increased Tesosterone

Question 23

WHat are the symptoms of 21-hydroxylase deficiency
Non-classical

Answer 23

Virillised Female Genetilia
Normal aldosterone and cortisol
Increased Testosterone

Question 24

What are the symptoms of Congenital Adrenal Hyoerplasia

Answer 24

Abnormal genitalia in girls (hence quicker diagnosis than males)
- clitoris may be enlarged and the urethra and vagina may merge
* Baby girls do not usually become seriously ill through complications (because of early diagnosis)
* Salt-wasting
* Hypotension
* Hyponatremia
* Hyperkalaemia
* Hypoglycaemia
* Outward signs of salt-wasting form include dehydration, vomiting, weight loss, extreme tiredness

Question 25

What is the treatment options for Congenital Adrenal Hyperplasia

Answer 25

Corticosteroids (oral hydrocortisone)- regulate blood glucose

Mineralcorticoids- oral fludrocortisone

Surgery to correct abnormal female genetelia- clitoroplasty

Mother can be given dexamethasone before birth.