Patient case (clinical description): 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's own account: 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.

Clinical trial: Whole Genome Sequencing in the Detection of Rare Undiagnosed Genetic Diseases in Children in China

Eligibility criteria:
Inclusion Criteria:

          1. Intelligence tests results of less than 40 (patients <3 years old using the Gesell
             Developmental Scale for screening; patients of 3-6 years old using Little Wechsler
             Intelligence Scale for screening; patients >6 years old using Old Wechsler
             Intelligence Scale for screening).

          2. Neurodevelopmental defects can be expressed as mental retardation, motor development
             retardation, language delay, epilepsy, etc. May have or not have Multiple congenital
             abnormalities, families with more than one affected patient will be enrolled priority

          3. Families went through at least one of the high throughput technology(WES or CMA) and
             receive the negative result

        Exclusion Criteria:

          1. Intellectual disability caused by pregnancy, perinatal infection, ischemia, and
             hypoxia and other non-hereditary causes,

          2. Obvious genetic metabolic diseases (such as different types of genetic metabolic
             diseases, bone disease, fragile X syndrome, etc.);
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.

Subject must be at most 18 Years

Eligibility (NLI label): Contradiction