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Information & Privacy Commission Guideline: Use & disclosure of genetic information without consent

 

This Information Bulletin notifies NSW public health organisations and staff of the publication of the "Use and disclosure of genetic information to a patient's genetic relatives: Guidelines for organisations in NSW" (the Guidelines) by the Information and Privacy Commission NSW and to advise that the Guidelines will take effect when the Health Legislation Amendment Act 2012 is proclaimed on 1 November 2014.

 

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Health behaviours can modify genetic risk

Reference
Friebel M et al. Modifiers of Cancer Risk in BRCA1 and BRCA2 Mutation Carriers: Systematic Review and Meta-Analysis  JNCI J Natl Cancer Inst (2014) 106(6): dju091

Pub Med link

Importance
The risk of breast cancer in woman carrying BRCA1 mutations is reduced if they had their first baby at a younger age. The risk was reduced by about 35% in women who were less than 30 at the time of their first baby’s birth, compared to women who were over 30 at the time of their first child’s birth.

Summary
Authors compiled 44 published papers and analysed the grouped results where papers were similar.   Many studies could not be pooled because they were quite different.   The most evidence was available for BRCA1 mutation carriers and breast cancer risk.  The only factor that provided sufficient and robust evidence to pool in a meta-analysis was mother’s age at the time of their first child’s birth. This showed that being younger at the time of the first child’s birth reduced the risk of developing breast cancer in women with a BRCA1 mutation.

Other factors such as breastfeeding, age at first menstruation, number of births, alcohol, caffeine, mammography, radiation, chest x-rays, oral contraceptive use, smoking and tamoxifen use were not sufficiently well or frequently studied to provide a pooled or consistent result.  Studies of BRCA2 on breast or ovarian cancer were too few and varied to provide pooled estimates. 

Media summary

Food during pregnancy can affect gene control

Reference
Dominguez-Salas P, et al Maternal nutrition at conception modulates DNA methylation of human metastable epialleles.  Nature Communications. DOI: 10.1038/ncomms4746  (29 April 2014)

Pub Med Link

Importance
We have always known that what a mother eats before and during pregnancy is important for the developing baby.  This study showed that the DNA of babies born to African women who conceived their children during a time of good food supply (dry season) had fewer chemical tags (methyl groups) on their DNA than babies conceived in the rainy season when food is less abundant. Fewer methyl-group tags on DNA means fewer genes are inactive, or turned off, in these cells.   Controlling which genes are turned on or off, when they are turned on or off and in what cells, is crucial for development and good health.

Summary
Researchers took blood samples every month from 30 women in several African villages and measured dietary indicators over a 12 month period. They used this data to estimate diet micronutrients in all women.  A second part of the study collected blood from women who became pregnant at the height of the rainy (hungry) season (n=84) or dry (harvest) season (n=83).  Four diet indicators were higher in the rainy seasons, four were lower and seven were the same.   Blood samples from these babies were tested for DNA tagging (methylation).  Babies conceived in the rainy season had more DNA tags than babies born during the dry, plentiful-food season.  A mothers’ body mass index and several diet indicators were predictive of DNA tagging.

Environmental factors influence heath and reproductive outcomes.  Epigenetics which includes DNA methylation (referred to above as DNA tagging) is a mechanism for this.

Media Summary

 

Correction of a genetic error

Reference
Yin
et al Genome editing with Cas9 in adult mice corrects a disease mutation and phenotype. Nature Biotechnology 2014; Online 31 March 2014

PubMed link

Importance
This is the first study showing that a genome editing system can be directed toward a specific sequence, it can replace the mutant sequence and it can be done via an injection far from the organ in which the cells need repairing.  The study reported that correction of a sequence in a small proportion of cells initially, appears to lead to positive selection for these cell types over a month of follow-upThe potential of this technology is an ability to correct a genetic mistake. While this information is very much preliminary, it provides some confidence that directed repair of mutations is a possibility.   

Summary
This study involved designing a genomic editing system, called CRISPR-Cas9 and injecting it into the tail of mice with a genetic disease called hereditary tyrosinaemia.  The aim was to correct the  disease causing mutation in a gene called FAH by chopping out the mutant form and inserting a version that would produce a normal functioning protein.  The experiments showed that 0.4% or about 1 in 250 cells contained the corrected sequence for the FAH gene after the single injection.  These mice showed either no disease or reduced disease in the 30 days following injection.  Thirty three days after treatment the mice were killed and their liver cells analysed.  These analyses showed that mice receiving one particular form of the editing system expressed the normal functioning form of the FAH protein in about 33% of their liver cells. This means that in some cells the disease causing gene was corrected and functional protein was able to be made from the corrected message.  The studies of the liver cells showed that there was a mixture of mutated and corrected versions of the gene message, with only a relatively minor amount of corrected message 8-36%, however this appeared to be sufficient to reduce the disease effects in these mice.

Media Summary

THE $1000 HUMAN GENOME SEQUENCE: What does it really mean?

 

January 2014: The Centre's Mona Saleh speaks on 2SER Radio

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Kissing Cousins: SBS Insight Program

On Tuesday 29th October, SBS TV’s Insight program discussed the risks and stigma associated with sexual relationships between biological relatives such as first cousins. This is known as consanguinity.

SBS Insight

More information and links to watch the program

 

Consanguinity is an accepted and important cultural practice in many parts of the world. When a couple are related biologically and plan on having children, there is an increased risk of having a child with a genetic condition. This risk varies depending on many factors and therefore it is important to access the correct information.

Fact sheet 16 gives detailed information about consanguinity

 

Heart of the Matter (Parts 1 and 2): ABC Catalyst Program

On Thursday 24th and 31st October, ABC TV’s Catalyst program discussed the issue of saturated fat in our diet, high cholesterol, heart disease and medications called statins. The program brought together a small number of people who believed that the association between saturated fat in the diet leading to high cholesterol and causing heart disease was not proven. This has stimulated great debate in the community with many experts challenging these ideas.

Catalyst; Heart of the matter

More information and links to watch the program

Importantly, there was agreement from both sides of the debate that people with the genetic condition of high cholesterol, called Familial hypercholesterolaemia, should be treated with statins if they are the appropriate age and condition, since their risk of heart disease is higher than average.

Familial hypercholesterolaemia (also know as FH) is an inherited condition that reduces the removal of cholesterol from the blood. This causes high cholesterol levels and early heart disease in some families. It affects about 1 in every 500 Australians.  In families with this condition, around half of the family members will have it and be at increased risk of early heart disease.

Fact sheet 53 gives detailed information about familial hypercholesterolaemia
Last updated: Nov 11, 2014