Genetic Counselling: Consanguinity and Cultural Expectations

Abstract

Individual and familial responses to diagnosis of serious genetic disorders are known to vary widely. But within some minority ethnic groups, expectations and norms may act as a further influence upon these responses and thus render genetic counselling more problematic than usual.

This paper explores the implications of these cultural influences for ‘transcultural’ genetic counselling by focusing upon familial responses to diagnosis of a neuro‐degenerative disorder, Juvenile Sandhoff disease. Five out of seven cases in the UK health districts were linked to an extended family. These factors, along with ambivalent feelings around tests for ‘carrier’ status, can in part be explained by culturally mediated factors that included fears about the future marital and social prospects of children and the reactions from within the local communities. Genetic counselling in such cases thus not only needs to focus on the individual and family, but also reflect an awareness of these complex interactions between culture and attitudes. Recent development in the identification of gene, substrate deprivation and other potential treatments are beginning to be evaluated.

Key Concepts:

  • Genetic counselling: consanguinity and cultural expectations.

  • Autosomal recessive mode of inheritance.

  • Sandhoff disease is a life limiting neuro‐degenerative disorder characterised by an accumulation of GM2 gangliosidosises particularly in neurons. GM2‐Gangliosidosis, type 11 Hexosaminidases A and B deficiency. Children with Juvenile Sandhoff disease have ataxia, motor delay, walking deterioration, spasticity, and autism and learning difficulties.

  • With random mating, it has been estimated that frequency of affected is 1 in 360000. However, literature (Drousiotou et al, Hum Genet. 2000 Jul; 107(1):12‐7) suggests potentially large variations in carrier frequency in different ethnic populations; prevalence of disease likely to be especially high in autozygous populations.

  • Regional DNA laboratory has identified A missense mutation in ex11 (c.1376c>A (p.Asp459Ala) in the affected probands.

  • Genetic testing could replace biochemical testing to ascertain the carrier status in families where Sandhoff disease has been diagnosed. This offers the opportunity for pre‐marital testing for carriers in addition to the service of pre‐natal diagnosis since this may be culturally acceptable and requested by these families.

  • Despite some previous assumptions, contemporary UK minority families may be keen to take on screening and pre‐natal diagnosis.

  • Many of these families are keen to take advantage of new treatments in future as they become available.

  • These universal responses may be overlain by culturally mediated concern.

  • Culturally skilled counsellors are needed to work successfully within our diverse population.

Keywords: transcultural; genetic counseling; consanguinity; Sandhoff's disease; hexoaminidase; gangliosidosis

Figure 1.

Family 1.

Figure 2.

Family 2.

Figure 3.

Family 3.

Figure 4.

Family 4.

Figure 5.

Family 5.

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Web Links

LocusID: 3074. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=3074 Hexosaminidase B (HEXB).

MIM number: 606873. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?606873 Hexosaminidase B (HEXB).

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How to Cite close
Karbani, Gulshan A(May 2012) Genetic Counselling: Consanguinity and Cultural Expectations. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0006179.pub2]