MOPD 1 and 3; Taybi-Linder Disease; Microcephalic Osteodysplastic Primordial Dwarfism 1 and 3

Taybi-Linder syndrome is a rare genetic disease caused by a mutation of the gene RNU4ATAC. It is characterized by bone and central nervous system malformations, in addition to intrauterine growth retardation (IGR). Taybi-Linder syndrome has been associated with incipient diabetes, electrolytic imbalances, hypothyroidism, hypothalamic disorders, hypogonadism, cryptorchidism, micropenis, and hypospadias.

Diagnostic testing: Prenatal diagnosis is of the utmost importance. Therefore, fetal ultrasound screening during the second trimester of pregnancy is necessary for diagnosis.

Diagnostic testing for Taybi-Linder syndrome may also include:

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  Genetic testing for the RNU4ATAC gene; and

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  MRI or other imaging showing brain abnormality.

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  Intrauterine and post-natal growth retardation;

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  Microcephaly (abnormally small head);

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  Skeletal dysplasia; and

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  Apnea.

Physical findings: Physical findings for Taybi-Linder syndrome may include:

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  Distinct facial features including sparse hair and eyebrows, sloped forehead with protruding eyes, and a flat nasal bridge with micrognathia (small jaw);

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  Dry skin;

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  Seizures;

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  Intellectual disability; and

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  Brain abrnormalities including lissencephaly (smooth brain), hypoplastic frontal lobes, agenesis of the corpus callosum or cerebellar vermis.

ICD-9: 758.9

ICD-10: Q87.1

This syndrome is often fatal in the first year of life. With improved genetic testing, individuals have been found in later childhood and adulthood—all with significant disability.

There is no curative treatment for Taybi-Linder syndrome. Facial abnormalities may require special considerations for airway management during anesthesia. Neurologic symptoms, such as seizures, can be managed medically.

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Positive genetic testing documenting presence of the RNU4ATAC gene; and

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  Neuropsychological testing documenting intellectual disability.

Suggested Listings for Evaluation:

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