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what is mutation of BRCA1 indcator of?

breast cancer


what is the normal function of BRCA1 and BRCA2?

are DNA repair proteins


what chromosome is BRCA1 found on?

chromosome 2


the BRCA1 and 2 mutations are only responsible for what percentage of familial cancers?

responsible for 16% of familial cancers


the mutation in BRCA1/2 account for what percentage of breast cancer? Is it different for people under the age of 35?

Account for 5-10% of all breast cancers
Responsible for 16% of breast cancer for females under the age of 35yrs


what is the average risk of a women getting breast cancer?

12% risk of developing breast cancer


what is the risk of a women getting breast cancer if they have the BRCA1/2 mutation?

BRCA1 or BRCA2 increases risk of breast cancer to 85%


what ther type of cancer has a increase in risk if there is mutation is BRCA1/2? By how much?

Increases risk of developing ovarian cancer from


what are the advantages to testing for BRCA mutations?

Women may feel relieved knowing for certain whether or not they are at a higher risk for breast cancer.

Women with breast cancer may have better responses to certain treatments that are specifically designed for BRCA positive patients (eg. cisplatin and PARP inhibitors).

Women may take preventive measures to help reduce their risk of breast cancer if they test positive for BRCA mutations (diet, exercising, tamoxifen).

Other family members may decide if they wish to be tested for BRCA mutations based on the results of a woman’s test.


what is the disadvantage of testing for the BRCA mutations?

Women may become worried, panicked, or stressed if they discover they have a higher than average risk for breast cancer.

Women who test positive for BRCA mutations are faced with the difficulty of telling family members (some of whom may also have the mutation).

Women who test negative for BRCA mutations may falsely believe they will never get breast cancer.

Women who test positive for BRCA mutations may have to deal with complications with health or life insurance


what is the reduction of risk of ovarian cancer if you reduce your ovaries after having a family?

reduces the risk by 85%


how effective is a Preventative mastectomy from developing breast cancer?

reduces the risk by 90%


what is Retinitis pigmentosa ?

a chronic hereditary eye disease characterized by black pigmentation and gradual degeneration of the retina.


what is Treacher Collins Syndrome?

Affects migration of neural crest cells --> in this syndrome the neural crest cell don’t fully make it

Narrowed chin and compressed airway --> need tracheotomy -->need to breathe through a tube


why is it important to get prenatal screaning for Treacher Collins Syndrome?

So pediatric surgeons know and can act straight away after the birth of the baby


what are the different prenatal diagnosis and when are they done?

Amniocentesis (~17 weeks)

Chorionic villus sampling (~11 weeks)


what is preimplantation diagnosis?

If you know the mother has the condition and the mother does not want to carry on the condition

Take the egg --> implant with sperm --> grow embryos

Take a cell from the embryo - see if the cells contains that condition if it does throw it away - if does not contain it then you implant that embryo


what monogenic disorders are preimplantation diagnosis used for?

Beta thalassemia
Sickle cell disae
Fragil X
Spinal muscular atrophy


what is Non-disclosure testing?

It is a test for HD
Without knowledge of disease status of the parent
To make sure the embryo does not have HD


what type of twins show there is some inheritance of obesity?

Dizygotic Twins


what is the inherited deficiency that causes obseity?

Leptin deficiency


How does leptin deficiency cause obesity?

Decrease food intake

Increase thermogenesis

Increase physical activity


how does leptin in a normal body work?

Mutation that codes for leptin
leptin produced by fat cells to targets the brain
tells it to reduce food intake
increase metabolism and increase exercise
this reduce fat intake and then this reduces the leptin increase and so regulation occurs


what is the treatment for leptin deficiency?

leptin replacemennt therapy


what is gene therapy?

Gene therapy is the use of genetic material- DNA or RNA- as a medicine.


what is classic gene therapy and what is the aim?

introduction of functional genes, in the form of DNA, to replace mutated genes.

Aim is to to repair mutated genes, silence overactive genes and to also provide our immune cells with the tools they need to recognise and kill cancer cells and infections


what is Leber’s congenital amaurosis (LCA?

Rare inherited eye disorder

Blindness at birth or in infancy

Accounts for 10-18% of congenital blindness

18 genes implicated

Recessive inheritance pattern


why is it effective to do gene therapy on eye?

Eye is immune privileged --> less likely for the immune body to attack
Eye is accessible for subretinal injection


what gene was identified to be a cause of LCA?

RPE65 mutations


how can you undo the RPE65 mutation?

Sub-retinal injection between RPE and photoreceptors with adeno-associated virus containing human RPE65 and human RPE65 promotor