- Hypertonia (HP:0001276): A condition in which there is increased muscle tone so that arms or legs, for example, are stiff and difficult to move. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:161800)
- 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:161800)
- Rigidity (HP:0002063): Continuous involuntary sustained muscle contraction. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:161800)
- Limb muscle weakness (HP:0003690): Reduced strength and weakness of the muscles of the arms and legs. Evidence: IEA. (OMIM:161800)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: IEA. (OMIM:161800)
- Feeding difficulties in infancy (HP:0008872): Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention. Evidence: IEA. (OMIM:161800)
- Waddling gait (HP:0002515): Weakness of the hip girdle and upper thigh muscles, for instance in myopathies, leads to an instability of the pelvis on standing and walking. If the muscles extending the hip joint are affected, the posture in that joint becomes flexed and lumbar lordosis increases. The patients usually have difficulties standing up from a sitting position. Due to weakness in the gluteus medius muscle, the hip on the side of the swinging leg drops with each step (referred to as Trendelenburg sign). The gait appears waddling. The patients frequently attempt to counteract the dropping of the hip on the swinging side by bending the trunk towards the side which is in the stance phase (in the German language literature this is referred to as Duchenne sign). Similar gait patterns can be caused by orthopedic conditions when the origin and the insertion site of the gluteus medius muscle are closer to each other than normal, for instance due to a posttraumatic elevation of the trochanter or pseudarthrosis of the femoral neck. Evidence: IEA. (OMIM:161800)
- Hyperlordosis (HP:0003307): Abnormally increased curvature (anterior concavity) of the lumbar or cervical spine. Evidence: IEA. (OMIM:161800)
- Type 1 muscle fiber predominance (HP:0003803): An abnormal predominance of type I muscle fibers (in general, this feature can only be observed on muscle biopsy). Evidence: IEA. (OMIM:161800)
- High palate (HP:0000218): Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective). Evidence: TAS. (OMIM:161800)
- Proximal muscle weakness (HP:0003701): A lack of strength of the proximal muscles. Evidence: IEA. (OMIM:161800)
- Frequent falls (HP:0002359). Evidence: IEA. (OMIM:161800)
- Spinal rigidity (HP:0003306): Reduced ability to move the vertebral column with a resulting limitation of neck and trunk flexion. Evidence: TAS. (OMIM:161800)
- Retrognathia (HP:0000278): An abnormality in which the mandible is mislocalised posteriorly. Evidence: IEA. (OMIM:161800)
- Neck flexor weakness (HP:0003722): Weakness of the muscles involved in neck flexion (sternocleidomastoid, longus capitus, longus colli, and scalenus anterior). Evidence: IEA. (OMIM:161800)
- Hyperreflexia (HP:0001347): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:161800)
- Dilated cardiomyopathy (HP:0001644): Dilated cardiomyopathy (DCM) is defined by the presence of left ventricular dilatation and left ventricular systolic dysfunction in the absence of abnormal loading conditions (hypertension, valve disease) or coronary artery disease sufficient to cause global systolic impairment. Right ventricular dilation and dysfunction may be present but are not necessary for the diagnosis. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:161800)
- 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: IEA. (OMIM:161800)
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: IEA. (OMIM:161800)
- Polyhydramnios (HP:0001561): The presence of excess amniotic fluid in the uterus during pregnancy. Evidence: IEA. (OMIM:161800)
- Generalized muscle weakness (HP:0003324): Generalized weakness or decreased strength of the muscles, affecting both distal and proximal musculature. Evidence: IEA. (OMIM:161800)
- EMG: neuropathic changes (HP:0003445): The presence of characteristic findings of denervation on electromyography (fibrillations, positive sharp waves, and giant motor unit potentials). Evidence: IEA. (OMIM:161800)
- Dysphagia (HP:0002015): Difficulty in swallowing. Evidence: IEA. (OMIM:161800)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: IEA. (OMIM:161800)
- Pes cavus (HP:0001761): An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight). Evidence: IEA. (OMIM:161800)
- Mask-like facies (HP:0000298): A lack of facial expression often with staring eyes and a slightly open mouth. Evidence: TAS. (OMIM:161800)
- Bulbar palsy (HP:0001283): Bulbar weakness (or bulbar palsy) refers to bilateral impairment of function of the lower cranial nerves IX, X, XI and XII, which occurs due to lower motor neuron lesion either at nuclear or fascicular level in the medulla or from bilateral lesions of the lower cranial nerves outside the brain-stem. Bulbar weakness is often associated with difficulty in chewing, weakness of the facial muscles, dysarthria, palatal weakness and regurgitation of fluids, dysphagia, and dysphonia. Evidence: IEA. (OMIM:161800)
- Areflexia (HP:0001284): Absence of neurologic reflexes such as the knee-jerk reaction. Evidence: IEA. (OMIM:161800)
- Respiratory insufficiency (HP:0002093). Evidence: IEA. (OMIM:161800)
- Mildly elevated creatine kinase (HP:0008180). Evidence: IEA. (OMIM:161800)
- Decreased fetal movement (HP:0001558): An abnormal reduction in quantity or strength of fetal movements. Evidence: IEA. (OMIM:161800)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: TAS. (OMIM:161800)
- Arthrogryposis multiplex congenita (HP:0002804): Multiple congenital contractures in different body areas. Evidence: IEA. (OMIM:161800)
- Neonatal hypotonia (HP:0001319): Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period. Evidence: IEA. (OMIM:161800)
- Respiratory insufficiency due to muscle weakness (HP:0002747). Evidence: IEA. (OMIM:161800)
- Slender build (HP:0001533): Asthenic habitus refers to a slender build with long limbs, an angular profile, and prominent muscles or bones. Evidence: IEA. (OMIM:161800)
- Nemaline bodies (HP:0003798): Nemaline rods are abnormal bodies that can occur in skeletal muscle fibers. The rods can be observed on histological analysis of muscle biopsy tissue or upon electron microscopy, where they appear either as extensions of sarcomeric Z-lines, in random array without obvious attachment to Z-lines (often in areas devoid of sarcomeres) or in large clusters localized at the sarcolemma or intermyofibrillar spaces. Evidence: IEA. (OMIM:161800)
- Autosomal dominant inheritance (HP:0000006): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: IEA. (OMIM:161800)
- Late-onset distal muscle weakness (HP:0003810). Evidence: IEA. (OMIM:161800)
- EMG: myopathic abnormalities (HP:0003458): The presence of abnormal electromyographic patterns indicative of myopathy, such as small-short polyphasic motor unit potentials. Evidence: IEA. (OMIM:161800)
These phenotypes are associated with the disease congenital myopathy 2a, typical, autosomal dominant (OMIM:161800).