Paternal transmission of a FMR1 full mutation allele.
Maria Isabel Alvarez-MoraMiriam GuitartLaia Rodriguez-RevengaIrene MadrigalElisabeth GabauMontserrat MilàPublished in: American journal of medical genetics. Part A (2017)
Fragile X syndrome (FXS) is the most common form of inherited intellectual disability (ID) and autism. In most of cases, the molecular basis of this syndrome is a CGG repeat expansion in the 5' untranslated region of the FMR1 gene. It is inherited as an X linked dominant trait, with a reduced penetrance (80% for males and 30% for females). Full mutation (FM) expansion from premutated alleles (PM) is only acquired via maternal meiosis, while paternal transmission always remains in the PM range. We present a 16-year-old girl with a mild fragile X syndrome phenotype. FMR1 gene study showed that the patient inherited a mosaic premutation-full mutation with an unmethylated uninterrupted allele (175, >200 CGG) from her father. The father showed an 88 CGG uninterrupted unmethylated allele in blood and sperm cells. To our knowledge, this is the first case of a FMR1 mosaic premutation-full mutation allele inherited from a PM father. In our opinion, the most likely explanation could be a postzygotic somatic expansion. We can conclude that in rare cases of a child with a full mutation whose mother does not carry a premutation, the possibility of paternal transmission should be considered.
Keyphrases
- intellectual disability
- particulate matter
- case report
- air pollution
- autism spectrum disorder
- genome wide
- copy number
- heavy metals
- healthcare
- induced apoptosis
- mental health
- risk assessment
- gene expression
- oxidative stress
- physical activity
- water soluble
- signaling pathway
- direct oral anticoagulants
- atrial fibrillation
- weight loss
- genome wide identification