Phenotypes associated with the disease infantile-onset X-linked spinal muscular atrophy (OMIM:301830):
- Facial palsy (HP:0010628): Facial nerve palsy is a dysfunction of cranial nerve VII (the facial nerve) that results in inability to control facial muscles on the affected side with weakness of the muscles of facial expression and eye closure. This can either be present in unilateral or bilateral form. Evidence: TAS. (OMIM:301830)
- Elevated circulating creatine kinase activity (HP:0003236): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:31932168)
- Inguinal hernia (HP:0000023): Protrusion of the contents of the abdominal cavity through the inguinal canal. Evidence: IEA. (OMIM:301830)
- Flexion contracture (HP:0001371): A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints. Evidence: TAS. (OMIM:301830)
- Myopathy (HP:0003198): A disorder of muscle unrelated to impairment of innervation or neuromuscular junction. Evidence: IEA. (OMIM:301830)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: IEA. Frequency: 1/1. (OMIM:301830)
- Severe muscular hypotonia (HP:0006829): A severe degree of muscular hypotonia characterized by markedly reduced muscle tone. Evidence: TAS. (OMIM:301830)
- Tongue fasciculations (HP:0001308): Fasciculations or fibrillation affecting the tongue muscle. Evidence: TAS. Frequency: 1/1. (OMIM:301830)
- Spinal muscular atrophy (HP:0007269): Muscular weakness and atrophy related to loss of the motor neurons of the spinal cord and brainstem. Evidence: TAS. (OMIM:301830)
- Neonatal onset (HP:0003623): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 1/1. (PMID:31932168)
- Myopathic facies (HP:0002058): A facial appearance characteristic of myopathic conditions. The face appears expressionless with sunken cheeks, bilateral ptosis, and inability to elevate the corners of the mouth, due to muscle weakness. Evidence: TAS. Frequency: 1/1. (OMIM:301830)
- Micropenis (HP:0000054): Abnormally small penis. At birth, the normal penis is about 3 cm (stretched length from pubic tubercle to tip of penis) with micropenis less than 2.0-2.5 cm. Evidence: IEA. (OMIM:301830)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: IEA. (OMIM:301830)
- Degeneration of anterior horn cells (HP:0002398). Evidence: IEA. (OMIM:301830)
- Areflexia (HP:0001284): Absence of neurologic reflexes such as the knee-jerk reaction. Evidence: TAS. Frequency: 1/1. (OMIM:301830)
- Respiratory insufficiency (HP:0002093). Evidence: IEA. (OMIM:301830)
- Persistent head lag (HP:0032988): The Premie-Neuro and the Dubowitz Neurological Examination score head lag in the same manner. Scoring for both is as follows: 0 = head drops and stays back, 1 = tries to lift head but drops it back, 2 = able to lift head slightly, 3 = lifts head in line with body, and 4 = head in front of body. This term applies if head lag persists beyond an expected age at a level of 0 or 1. Persistent head lag beyond age 4 mo has been linked to poor outcomes. Evidence: PCS. Frequency: 1/1. (PMID:31932168)
- Decreased compound muscle action potential amplitude (HP:0033383): Reduced level of the compound muscle action potential (CMAP), which is recorded following electrical stimulation of a nerve from surface electrodes overlying a muscle supplied by that nerve. Evidence: PCS. Frequency: 1/1. (PMID:31932168)
- X-linked recessive inheritance (HP:0001419): A mode of inheritance that is observed for recessive traits related to a gene encoded on the X chromosome. In the context of medical genetics, X-linked recessive disorders manifest in males (who have one copy of the X chromosome and are thus hemizygotes), but generally not in female heterozygotes who have one mutant and one normal allele. Evidence: PCS. (PMID:18179898)
- Abnormality of metabolism/homeostasis (HP:0001939). Evidence: IEA. (OMIM:301830)
- Multiple joint contractures (HP:0002828). Evidence: TAS. (OMIM:301830)
- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: IEA. (OMIM:301830)
- Arthrogryposis multiplex congenita (HP:0002804): Multiple congenital contractures in different body areas. Evidence: TAS. (OMIM:301830)
- Decreased fetal movement (HP:0001558): An abnormal reduction in quantity or strength of fetal movements. Evidence: TAS. (OMIM:301830)
- Respiratory insufficiency due to muscle weakness (HP:0002747). Evidence: TAS. (OMIM:301830)
- Hypospadias (HP:0000047): Abnormal position of urethral meatus on the ventral penile shaft (underside) characterized by displacement of the urethral meatus from the tip of the glans penis to the ventral surface of the penis, scrotum, or perineum. Evidence: TAS. (OMIM:301830)
- Cryptorchidism (HP:0000028): Testis in inguinal canal. That is, absence of one or both testes from the scrotum owing to failure of the testis or testes to descend through the inguinal canal to the scrotum. Evidence: IEA. (OMIM:301830)
- Micrognathia (HP:0000347): Developmental hypoplasia of the mandible. Evidence: IEA. (OMIM:301830)
- Weak cry (HP:0001612). Evidence: PCS. Frequency: 1/1. (PMID:31932168)