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3q29 deletion syndrome is caused by a heterozygous 1.6 Mb deletion on chromosome 3, which occurs in about 1 in 30 000 births. Phenotypic features of this syndrome include mild-to-moderate intellectual disability, autism spectrum disorder, slightly dysmorphic facial features, ataxic gait, and chest-wall deformity. Gastrointestinal disorders, dental abnormalities, feeding problems during infancy, recurrent ear infections, and heart defects have also been observed. Since the incidence of the deletion is rare, the phenotype has not been fully described, particularly in adults. This report describes a young adult female with 3q29 deletion syndrome, autism spectrum disorder, intellectual disability, and anxiety who experienced a sustained, non-medication induced paroxysmal oculogyric dystonia which responded to anticholinergic and antihistaminic medications. This is the first report of paroxysmal oculogyric dystonia associated with this deletion, possibly expanding the phenotypic features of this microdeletion syndrome.

We evaluated myoblast implantation therapy in three subjects with Becker muscular dystrophy who received 60 million myoblasts in one tibialis anterior (TA) muscle 2 months after beginning cyclosporine immunosuppression (5 to 10 mg/kg) that continued for 1 year. Strength of the implanted and control TA muscles was measured before and after treatment using a gauge to record TA contraction force. Our protocol controlled for the effects of cyclosporine and myoblast injections. In this pilot study, myoblast implantation did not improve strength of the implanted TA muscles.

One of the major limitations of myoblast implantation as a therapy for muscular disease is that multiple injections by intramuscular implantation may be required for widespread delivery of cells. Also, some sites (eg, the diaphragm) are relatively inaccessible to injection. As an alternative, we have undertaken intra-arterial administration of myoblasts. For these experiments, we used donor cell myoblasts from the immortal L6 cell line labeled with lacZ via the beta-gal-at-gal retrovirus. In our model, target rat skeletal muscle (tibialis anterior [TA]) was injured using 0.5 ml of 0.5% bupivacaine and 15 IU of hyaluronidase; saline was injected into the contralateral side as a control. We infused 3 x 10(6) lacZ-positive cells into the abdominal aorta of previously injured, immunosuppressed (cyclosporine A) rats. At 7, 14, and 28 days, TA, liver, heart, lung, and spleen were examined for lacZ staining. In both the injured and control muscles, a few differentiated, lacZ-positive muscle cells were present, both singly and in groups, at each time point. These studies demonstrate that genetically labeled, transformed myoblasts may migrate from the arterial circulation to muscle and fuse there to form differentiated muscle cells. It is conceivable that intra-arterial delivery of myoblasts may have a role in the therapy of selected diseases of skeletal muscle.