Non-skewed X-inactivation may cause mental retardation in a female carrier of X-linked alpha-thalassemia/mental retardation syndrome (ATR-X): X-inactivation study of nine female carriers of ATR-X.

Abstract

X-linked alpha-thalassemia/mental retardation syndrome (ATR-X) is a syndromic form of X-linked mental retardation. We investigated the X-inactivation status of nine female ATR-X carriers by methylation-specific PCR of the HUMARA gene. Six carriers demonstrated a skewed X-inactivation pattern (>90:10) and one showed a non-skewed pattern (72:28), while two were uninformative because of homozygosity for the CAG repeat polymorphic alleles in the HUMARA. Only the carrier mother who showed non-skewed X-inactivation had moderate mental retardation. These findings suggest that mutations in ATRX may cause mental retardation in females, if the X chromosome carrying mutated ATRX is not properly inactivated.

• Authors: Takahito Wada, Hideo Sugie, Yoshimitsu Fukushima, Shinji Saitoh
• Journal: American journal of medical genetics. Part A (Am J Med Genet A) Vol. 138 Issue 1 Pg. 18-20 (Sep 15 2005) ISSN: 1552-4825 [Print] United States
• PMID: 16100724 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: (c) 2005 Wiley-Liss, Inc.

Chemical References

• AR protein, human
• Nuclear Proteins
• Receptors, Androgen
• DNA Helicases
• ATRX protein, human
• X-linked Nuclear Protein

Topics

• Chromosomes, Human, X (genetics)
• DNA Helicases (genetics)
• DNA Methylation
• Dosage Compensation, Genetic
• Female
• Genetic Linkage
• Heterozygote
• Humans
• Mental Retardation, X-Linked (genetics)
• Mutation
• Nuclear Proteins (genetics)
• Polymerase Chain Reaction (methods)
• Receptors, Androgen (genetics)
• X-linked Nuclear Protein
• alpha-Thalassemia (genetics)