Clinical trial: NIPD on cffDNA for Triplet Repeat Diseases (NCT04698551)

Eligibility criteria:
Inclusion criteria:

          -  Couple at risk (based on family history or echographic findings) for one of the
             following diseases: Huntington's disease, Steinert's myotonic dystrophy, fragile X

          -  Written informed consent was obtained for DIACCIMEX study and mentionned
             "authorization for use for further studies on familial pathology. Indeed, the DNA can
             be used anonymized for the development of new analyzes of non-invasive prenatal
             diagnosis".

          -  Prenatal diagnosis has been done for the pregnancy during which maternal blood has
             been collected

          -  Couple molecular diagnosis results for one of the following diseases (Huntington's
             disease, Steinert's myotonic dystrophy, fragile X and spinocerebellar ataxias 1, 2 or
             3 ) MUST BE AVAILABLE.

        Exclusion criteria:

          -  Couple Genomic DNA are unavailable

          -  Subjects at risk of transmitting the family disease, but not wishing to know their
             molecular status

          -  Individuals under guardianship by court order
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Months old.


Patient description (medical language): A 15-year-old boy with mild intellectual disability is brought to the office by his parents for a routine physical examination.  The boy is going to a school for students with learning disabilities.  The patient was adopted, and his immunizations are up to date.  Review of the patient's medical records is notable for cytogenetic studies that showed a small gap near the tip of the long arm of the X chromosome, which is consistent with fragile X syndrome, an X-linked disorder. The defect is an unstable expansion of trinucleotide repeats (CGG) in the fragile X mental retardation 1 (FMR1) gene, located on the long arm of the X chromosome. He is not using any medications and vital signs are within normal levels. His blood chemistry analysis as bellow:
Blood Chemistry Value      Normal Range     Patient Value
Glucose                    90-120 mg/dl     95 mg/dl
BUN (Blood Urea Nitrogen)  7-24 mg/dl       10 mg/dl
Creatinine                 0.7-1.4 mg/dl    0.8 mg/dl
Calcium                    8.5-10.5 mg/dl   9 mg/dl
Sodium                     134-143 mEq/L    135 mEq/L
Potassium                  3.5-4.5 mEq/L    3.7 mEq/L
Chloride                   95-108 mEq/L     98 mEq/L
CO2                        20-30 mEq/L      25 mEq/L
Blood pH                   7.38-7.42        7. 39

Patient description (patient's own words): My husband and I brought our 15-year-old son to the clinic for his routine exam. My son is going to school for special needs students. We adopted him a few years ago. His vaccinations are up to date. He already passed some chromosome testing and they found that he has a fragile X syndrome. The doctor told us that it comes from repeats in the fragile X chromosome. My son is not using any medication and his blood pressure temperature and breathing were normal during the exam. He also did a blood test. The results came back and showed that his blood sugar urea creatinine calcium sodium potassium chloride CO2 and blood pH were all within the normal range.

Does the patient match the trial criteria? 0