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Human Genetics

, Volume 121, Issue 1, pp 43–48 | Cite as

Homozygosity mapping in consanguineous families reveals extreme heterogeneity of non-syndromic autosomal recessive mental retardation and identifies 8 novel gene loci

  • Hossein Najmabadi
  • Mohammad Mahdi Motazacker
  • Masoud Garshasbi
  • Kimia Kahrizi
  • Andreas Tzschach
  • Wei Chen
  • Farkhondeh Behjati
  • Valeh Hadavi
  • Sahar Esmaeeli Nieh
  • Seyedeh Sedigheh Abedini
  • Reza Vazifehmand
  • Saghar Ghasemi Firouzabadi
  • Payman Jamali
  • Masoumeh Falah
  • Seyed Morteza Seifati
  • Annette Grüters
  • Steffen Lenzner
  • Lars R. Jensen
  • Franz Rüschendorf
  • Andreas W. Kuss
  • H. Hilger Ropers
Original Investigation

Abstract

Autosomal recessive gene defects are arguably the most important, but least studied genetic causes of severe cognitive dysfunction. Homozygosity mapping in 78 consanguineous Iranian families with nonsyndromic autosomal recessive mental retardation (NS-ARMR) has enabled us to determine the chromosomal localization of at least 8 novel gene loci for this condition. Our data suggest that in the Iranian population NS-ARMR is very heterogeneous, and they argue against the existence of frequent gene defects that account for more than a few percent of the cases.

Keywords

Down Syndrome Intelligence Quotient Consanguineous Family GJB2 Gene Homozygosity Mapping 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

We thank Jürg Ott for his advice concerning the significance levels of LOD scores in whole genome linkage studies, and Hannelore Markert for assisting us with the preparation of the manuscript. We are grateful to all patients, parents and other relatives for their active participation in this study, and to numerous genetic counselors and other health care professionals for their assistance. This study would not have been possible without support from the Deputy of Research, Iranian Ministry of Health and Medical Education (to HN) and a grant of the Max Planck Innovation Funds (to HHR).

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Hossein Najmabadi
    • 1
  • Mohammad Mahdi Motazacker
    • 2
  • Masoud Garshasbi
    • 2
  • Kimia Kahrizi
    • 1
  • Andreas Tzschach
    • 2
  • Wei Chen
    • 2
  • Farkhondeh Behjati
    • 1
  • Valeh Hadavi
    • 3
  • Sahar Esmaeeli Nieh
    • 1
  • Seyedeh Sedigheh Abedini
    • 1
  • Reza Vazifehmand
    • 1
  • Saghar Ghasemi Firouzabadi
    • 1
  • Payman Jamali
    • 1
  • Masoumeh Falah
    • 1
  • Seyed Morteza Seifati
    • 1
  • Annette Grüters
    • 4
  • Steffen Lenzner
    • 2
  • Lars R. Jensen
    • 2
  • Franz Rüschendorf
    • 5
  • Andreas W. Kuss
    • 2
  • H. Hilger Ropers
    • 2
  1. 1.Genetics Research CentreUniversity of Social Welfare and Rehabilitation SciencesTehranIran
  2. 2.Department Human Molecular GeneticsMax Planck Institute for Molecular GeneticsBerlinGermany
  3. 3.Genetic and Pathology LaboratoryTehranIran
  4. 4.Department of Paediatric EndocrinologyOtto Heubner Centre for PaediatricsBerlinGermany
  5. 5.Gene Mapping CentreMax Delbrück Centre for Molecular MedicineBerlinGermany

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