FMR1 and fragile X syndrome: Two were in individuals hemizygous for de novo 5′UTR deletions tested due to family history of FXS, a 19-month-old male with c.-156_-69del and no neurological or physical findings, and a 10-year-old female with c.-196_-40del in trans with a large deletion including FMR1 but no typical phenotype for FXS (only features were low birthweight, early thelarche, hearing loss, perinatal asphyxia with 6-week ICU stay) [34,35].