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With the rapid development of artificial intelligence (AI) technology and an increasing demand for redundant robotic systems, robot control systems are becoming increasingly complex. Although forward kinematics (FK) and inverse kinematics (IK) equations have been used as basic and perfect solutions for robot posture control, both equations have a significant drawback. When a robotic system is highly nonlinear, it is difficult or impossible to derive both the equations. In this paper, we propose a new method that can replace both the FK and IK equations of a seven-degrees-of-freedom (7-DOF) robot manipulator. This method is based on reinforcement learning (RL) and artificial neural networks (ANN) for supervised learning (SL). RL was used to acquire training datasets consisting of six posture data in Cartesian space and seven motor angle data in joint space. The ANN is used to make the discrete training data continuous, which implies that the trained ANN infers any new data. Qualitative and quantitative evaluations of the proposed method were performed through computer simulation. The results show that the proposed method is sufficient to control the robot manipulator as efficiently as the IK equation.

<b><i>Background:</i></b> <i>PHF21A</i>, along with <i>EXT2</i> and <i>ALX4</i>, is one of the causative genes of Potocki-Shaffer syndrome (PSS), a rare contiguous disorder involving chromosome region11p11.2. <i>PHF21A</i> has been associated with intellectual developmental disorders and craniofacial anomalies and suggested as a candidate for more extended phenotypes. However, variants in <i>PHF21A</i> and its associated phenotypes are yet to be fully explored, since reports on cases with variants affecting this gene are few worldwide. We present a novel heterogeneous variant in <i>PHF21A</i> in a 26-year-old Korean female. <b><i>Methods:</i></b> The patient’s clinical manifestations were recorded and physical examination, cognitive assessment, brain imaging, metabolic screening, and cytogenetic testing including whole exome sequencing were pursued. <b><i>Results:</i></b> Whole exome sequencing identified a de novo nonsense variant c.1171A&#x3e;T (p.Lys391Ter), affecting the AT-hook domain. The patient showed an extended phenotypic spectrum along with intellectual developmental disorders and craniofacial anomalies, such as attention-deficit hyperactivity disorder, epilepsy, overgrowth, and hypotonia. Variants affecting the AT-hook domain are few in PSS, however, the phenotypic spectrum of the patient was in line with previously reported cases. <b><i>Conclusion:</i></b> This case further reinforced and adds to the extended data on the phenotypes associated with <i>PHF21A</i> haploinsufficiency.