Transcript Using assessments of biological and genetic risk to inform policy

Using assessments of biological
and genetic risk to inform policy
priorities:
A community perspective
Dr Pritti Mehta
Programme Manager (Equity and Access)
Genetic Interest Group
Key questions?
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What factors cause ethnic inequalities in health?
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To what extent do genetic risk factors contribute to
population or ethnic differences in health?
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Do concepts of race or ethnicity have any biological
meaning?
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How to use this information to inform policy priorities
that will achieve beneficial societal outcome?
Understanding and tackling ethnic
inequalities in health
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Differential access to services
Quality of services
Social and cultural influences
Genetic/biological variation
Foetal programming
Migration
Life events
Socio-economic factors
Racial discrimination
Insufficient research to identify and address the underlying
causes of variation
To what extent do genetic risk factors
contribute to population or ethnic
differences in health?
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Mendelian disorders: such Sickle Cell Disease and Tay Sachs
which have a clear genetic basis and show variation in
prevalence across population or ethnic groups due to unequal
distribution of the disease causing alleles
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Multi-factorial common conditions: Although minority ethnic
groups are often disproportionately affected - the genetic basis
is still unclear and therefore need for further research to
investigate gene –environment interactions in multiple
populations in order to answer these questions
Do concepts of race or ethnicity have
any biological meaning?
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Meeting convened at the National Human Genome
Centre at Howard University in Washington, D.C. on
15th May 2003 titled “Human Genome Variation and
Race: The State of the Science”. Brought together
experts in sociology, anthropology, history and
genetics
Background
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Advent of molecular genetics and sequencing of the
human genome
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Recent common genetic origin in Africa
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Greater genetic variation within populations that between
populations
These findings have lead to many well-intentioned
statements by geneticists suggesting there is no
connection between race/ethnicity and human genetic
variation
Where the consensus lies?
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Increasing scientific evidence that human genetic variation
is geographically structured – most individuals form the
same geographic region will be more similar to one another
than to individuals form a distant region.
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Genetic variation is continuous and overlapping and
therefore populations are never pure with definite
boundaries between individuals or populations (e.g. normally
ascribed to races).
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Rainbows within rainbows….. Groups identified by ethnic or
geographic labels maybe genetically highly internally
structured.
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Worldwide patterns of genetic variation not well understood.
Where the dispute lies?
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How to represent that portion of variation that does
correlate with geography?
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Because there is some correlation between geographical
origin and ethnicity/race it would be misleading to say that
there is no connection between ethnicity and genetic
variation
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However the connection is quite blurry because of multiple
other non-genetic components of ethnicity, the lack of
defined boundaries between populations and the fact that
many individuals have mixed ancestry.
Francis Collins: US Director of the US
National Human Genome Research
Institute (NHGRI)
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True understanding of disease risk requires us to go
well beyond these weak imperfect proxy relationships;
and
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If we are not satisfied with imperfect surrogates in
trying to understand hereditary causes, then we should
not be satisfied with them as measures of
environmental causation either.
Conclusions
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Assessment of geographical origin, ancestry, or
even race/ethnicity to determine genetic risk
may in some cases prove biomedically useful.
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However direct assessment of the underlying
genetic variation will ultimately yield more
useful information.
How to use this information to inform
policy priorities
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Translating these finding into policy principles will not be easy
or straight-forward
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Risk assessments based on population differences or ethnicity
should be properly assessed, with attempts made to remedy
situations in which the use of such information is misleading or
couter-productive
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Population affiliations alone maybe crude indicators e.g. failure
to diagnose sickle cell disease in a European or cystic fibrosis
in an Asian individual
How to use this information to inform
policy priorities
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Proper consultation with community groups to assess
acceptability and the psychosocial impact of these risk
assessments
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However these debates should not hamper progress towards
identifying new genetic knowledge that might benefit vulnerable
groups: Such as the need to carry out well-designed, large scale
studies in multiple populations to identify underlying disease
risk factors
UK Biobank
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UK Biobank: large scale prospective cohort study that aims to
identify genetic and environmental influences on common
disease
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Planning to sample minorities in proportion to the total UK
population
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Will effectively exclude minorities because the numbers
collected will not be sufficient to provide information about
gene–environment interactions specific to those groups
UK Biobank
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this will prejudice our knowledge
of the genetic and environmental
determinants of disease and may lead to
greater inequalities in health.
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strongly support Francis Collins view
that over-recruitment of minorities is an
essential component of any prospective
cohort study of genes and environment. (Collins
2004).
Concerns
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The inability to effectively inform policy and practice
towards research and service delivery -
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May indeed widen ethnic health inequalities that arise
from biological/genetic variation, due to knowledge
gaps and resulting differential access to diagnosis and
treatment options
Responding to community specific
needs
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A recent study in a UK child development centre
in Bradford found that the prevalence of many
non-malignant life threatening conditions was
almost double the national average.
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Here 42% of births are of Pakistani origin
Communication of risk
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Need to develop linguistically and culturally
appropriate and accessible forms of communication to
inform and raise awareness about different risk
assessment programmes
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Develop these through consultation with target groups
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Note that concepts of risk can vary from individual to
individual
Community consultation comments
On cousin marriage:
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‘Make it clear, very sensitively so as to not sound like you are
attacking individuals, cultures, religious beliefs, etc…, that interfamily marriage increases risk of recessive genetic diseases,
but not dominant genetic diseases., But don’t exaggerate the
risk.. Explain that it depends on the specific disease/ individual/
relationship between 2 specific people’
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‘Must be very careful, as one misunderstanding can lead to the
whole thing being misinterpreted, i.e., communities feeling as
though you are attacking their particular culture’
Community consultation comments
On pre-implantation diagnosis:
 ‘pregnancy termination is unthinkable for many
people of different cultures and may be
religions. For Somalis in Somalia and of course
many in here it is not an option. The leaflet
should clearly state that if you are carrying a
foetus with genetic disorder, termination is not
compulsory nor the only option’
Thank you