Genetic Counselling

L.O: to explain the role of a genetic counsellor

Starter: What sources of information might a genetic counsellor use when examining if a baby has a genetic disease? (Think back to last lesson…)

Sources of information that a genetic counsellor would use when assessing a case

Sources of information that a genetic counsellor would use when assessing a case

Chorionic Villi

Sampling

Amniocentesis

Sources of information that a genetic counsellor would use when assessing a case

Chorionic Villi

Sampling

Amniocentesis Parental Blood Test

Family History

Observable characteristics

Ultra sound

Genetic Counsellors

Definition: provide information and support to families who have members with birth defects or genetic disorders and to families who may be at risk of a variety of inherited conditions.

Past Exam Questions

Past Exam Questions

Past Exam Questions

Past Exam Questions

Past Exam Questions

• http://www.youtube.com/watch?v=0enUQ2dxq9Q 5 mins onwards

Cystic FibrosisCystic Fibrosis6. Genetic Screening

5. Gene Therapy

4. Treatments

2. Mutation

3. Mode of Inheritance

1. Affected Areas

(Stick body pic here and fill in labels)

2. Mutation2. MutationA deletion on chromosome 7 causes a faulty

protein (CFTR) to be made. The CFTR usually transports Cl- out of cells, lowering the water potential outside and so water will move outside of the cell by osmosis.

The faulty protein does not allow Cl- to leave the cell, so water does not move outside the cell to dilute the mucus. Therefore, the mucus is thicker and this makes breathing difficult.

3. Mode of Inheritance3. Mode of InheritanceCF is caused by a r_________ allele, so you

need _ copies to express it (h_________).

25% of the population are carriers (h________) therefore are unaffected and unaware they carry the CF allele.

A punnet square / genetic cross to show two carrier parents: (use a ruler to draw a genetic cross here)

4. Treatments4. Treatments(From Fridays video, you should be able to

write a couple of full sentences (not bullet points!) on CF treatments / ways it is managed)

5. Gene Therapy5. Gene Therapy

6. Genetic Screening6. Genetic Screening

Huntington’s Disease – Huntington’s Disease – a neurological disorder a neurological disorder of the central nervous of the central nervous

system that causes system that causes progressive progressive

degeneration of brain degeneration of brain cellscells

6. Genetic Screening

6. Gene Therapy

5. Treatments

3. Mutation

4. Mode of Inheritance

1. Affected Areas

(Draw and label a picture of a neurone here)

2. Symptoms

http://www.youtube.com/watch?v=ht37KNcMAl4

3. Mutation3. MutationA mutation of the Huntingtin gene on

chromosome 4 causes ‘CAG’ to be repeated, over the normal level of 35 times. This increases the size of the protein made, which is then cut into smaller, toxic fragments. These bind together and accumulate in neurones. However, the exact science of how this occurs is unknown.

4. Mode of Inheritance4. Mode of InheritanceHD is caused by a d_________ allele, so you

need _ copy to express Huntingtons Disease.

A punnet square / genetic cross to show an affected heterozygous parent, with a unaffected parent: (use a ruler to draw a genetic cross here)

5. Treatments5. Treatments(From Fridays video, you should be able to

write a couple of full sentences (not bullet points!) on CF treatments / ways it is managed)

6. Gene Therapy6. Gene Therapy

7. Genetic Screening7. Genetic Screeninghttp://www.bbc.co.uk/news/10454649