An unusual fragile X sibship: female compound heterozygote and male with a partially methylated full mutation
| Autor: | F. Cogliati, M. Macchi, Lidia Larizza, S. Russo, V. Briscioli, Faustina Lalatta |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Male
Heterozygote X Chromosome Intelligence Nerve Tissue Proteins Neuropsychological Tests Biology Sister Compound heterozygosity Methylation Nuclear Family Cytogenetics Fragile X Mental Retardation Protein Sex Factors Genetics medicine Humans Genetics (clinical) X chromosome Intelligence Tests Intelligence quotient Chromosome Fragility RNA-Binding Proteins Wechsler Adult Intelligence Scale DNA medicine.disease Brother Pedigree Developmental disorder Fragile X Syndrome Mutation Mutation (genetic algorithm) Female Trinucleotide Repeat Expansion |
| Zdroj: | Clinical Genetics. 54:309-314 |
| ISSN: | 0009-9163 |
| DOI: | 10.1034/j.1399-0004.1998.5440408.x |
| Popis: | We describe here a fragile X sibship of borderline retarded sister and brother born to carrier parents. The sister is a compound heterozygote (with a full mutation on one X chromosome and a pre-mutation on the other X chromosome). The brother has a partially methylated full mutation. The activation ratio (AR) for the sister's pre-mutation was 0.69 and the percent lack of methylation for the brother's full mutation was 73%. Intellectual and neuropsychological Wechsler Adult Intelligence Scale (W.A.I.S.) achievement tests reported full scale IQ scores of 74 in the sister and 77 in the brother. A significant discrepancy between verbal and performance IQ was found in the sister, indicating that her main impairment was in the cognitive area. The parents of this unusual sibship came from a small village, as did one of the two previously described cases of compound heterozygous females. These rare females raise special issues for genetic counselling in fragile X carrier couples, the frequency of which remains to be defined in different populations. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text