Identification of fragile X pre-mutation carriers in the Chinese obstetric population using a robust FMR1 polymerase chain reaction assay: implications for screening and prenatal diagnosis.
Hong Kong Med J
; 23(2): 110-6, 2017 Apr.
Article
en En
| MEDLINE
| ID: mdl-28253484
ABSTRACT
INTRODUCTION:
There is significant morbidity associated with fragile X syndrome. Unfortunately, most maternal carriers are clinically silent during their reproductive years. Because of this, many experts have put forward the notion of preconception or prenatal fragile X carrier screening for females. This study aimed to determine the prevalence of fragile X syndrome pre-mutation and asymptomatic full-mutation carriers in a Chinese pregnant population, and the distribution of cytosine-guanine-guanine (CGG) repeat numbers using a robust fragile X mental retardation 1 (FMR1) polymerase chain reaction assay.METHODS:
This was a cross-sectional survey in prospectively recruited pregnant women from a university hospital in Hong Kong. Chinese pregnant women without a family history of fragile X syndrome were recruited between April 2013 and May 2015. A specific FMR1 polymerase chain reaction assay was performed on peripheral blood to determine the CGG repeat number of the FMR1 gene. Prenatal counselling was offered to full-mutation and pre-mutation carriers.RESULTS:
In 2650 Chinese pregnant women, two individuals with pre-mutation alleles (0.08%, one in 1325) and one asymptomatic woman with full-mutation (0.04%, one in 2650) alleles were identified. The overall prevalence of pre-mutation and full-mutation alleles was 0.11% (1 in 883). Furthermore, 30 (1.1%) individuals with intermediate alleles were detected. In the 2617 women with normal CGG repeats, the most common CGG repeat allele was 30.CONCLUSIONS:
The overall prevalence of pre-mutation and asymptomatic full-mutation carriers in the Chinese pregnant population was one in 883, detected by a new FMR1 polymerase chain reaction assay.Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Diagnóstico Prenatal
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Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil
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Síndrome del Cromosoma X Frágil
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Tamización de Portadores Genéticos
Tipo de estudio:
Diagnostic_studies
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Observational_studies
/
Prevalence_studies
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Prognostic_studies
/
Risk_factors_studies
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Screening_studies
Límite:
Adult
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Female
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Humans
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Pregnancy
País/Región como asunto:
Asia
Idioma:
En
Revista:
Hong Kong Med J
Asunto de la revista:
MEDICINA
Año:
2017
Tipo del documento:
Article
País de afiliación:
Hong Kong