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Prevalence of classical phenylketonuria in mentally retarded individuals in Iran

N M Ghiasvand1, A Aledavood, R Ghiasvand

  • 1Department of Biology, Grand Valley State University, Allendale, MI 49401, USA. ghiasvan@gvsu.edu

Journal of Inherited Metabolic Disease
|September 22, 2009
PubMed

Insights

Phenylketonuria (PKU) prevalence in Iran is high, affecting 2.1% of individuals with intellectual disabilities. A nationwide newborn screening program for PKU is recommended, potentially combined with congenital hypothyroidism screening, for cost-effectiveness.

Area of Science:

  • Medical Genetics
  • Public Health
  • Biochemistry

Background:

  • Phenylketonuria (PKU) is a genetic disorder.
  • Intellectual disability is a common outcome of untreated PKU.
  • Iran has a unique PKU referral pattern.

Purpose of the Study:

  • To determine the prevalence of PKU in individuals with intellectual disabilities in Iran.
  • To compare PKU prevalence in different regions of Iran.
  • To inform recommendations for PKU screening programs in Iran.

Main Methods:

  • Guthrie Biological Inhibition Assay was used for screening.
  • 4963 individuals with intellectual disabilities were screened across 31 cities and towns.
  • Data was analyzed based on geographical location and shelter housing.

Main Results:

  • The average PKU prevalence was 2.1%, higher than in other countries before newborn screening.
  • PKU prevalence was 2.81% in Tehran shelters and 1.68% in other shelters.
  • Higher prevalence in Tehran may be due to referral patterns.

Conclusions:

  • High PKU prevalence in Iran suggests a high incidence in neonates.
  • High PKU allele frequency and consanguinity likely contribute to prevalence.
  • A nationwide PKU screening program, possibly with congenital hypothyroidism screening, is cost-effective and warranted.

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