Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).

Absence of a testis from the scrotum on one side owing to failure of the testis or testes to descend through the inguinal canal to the scrotum.

Clubfoot is a congenital limb deformity defined as fixation of the foot in cavus, adductus, varus, and equinus (i.e., inclined inwards, axially rotated outwards, and pointing downwards) with concomitant soft tissue abnormalities (Cardy et al., 2007). Clubfoot may occur in isolation or as part of a syndrome (e.g., diastrophic dysplasia, 222600). Clubfoot has been reported with deficiency of long bones and mirror-image polydactyly (Gurnett et al., 2008; Klopocki et al., 2012).

Increased back to front length of the foot.

Toes that appear disproportionately long compared to the foot.

Increased dimensions of the Virchow-Robin spaces (also known as perivascular spaces), which surround the walls of vessels as they course from the subarachnoid space through the brain parenchyma. Perivascular spaces are commonly microscopic, and not visible on conventional neuroimaging. This term refers to an increase of size of these spaces such that they are visible on neuroimaging (usually magnetic resonance imaging). The dilatations are regular cavities that always contain a patent artery.

Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.

Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.

Constipation for longer than three months with fewer than 3 bowel movements per week, straining, lumpy or hard stools, and a sensation of anorectal obstruction or incomplete defecation.

The presence of chronic diarrhea, which is usually taken to mean diarrhea that has persisted for over 4 weeks.

An inadequate sucking reflex, resulting in the difficult of newborns to be breast-fed.

Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires).

A febrile seizure is any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in children between the ages of 3 months and 6 years.

Difficulty initiating sleep, that is, increased sleep onset latency, refers to the condition where it takes 30 minutes or more to fall asleep.

A degree of language development that is significantly below the norm for a child of a specified age.

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

Persistent deficits in social interaction and communication and interaction as well as a markedly restricted repertoire of activity and interest as well as repetitive patterns of behavior.

Attention-deficit/hyperactivity disorder (ADHD) is a behavioral disorder that typically begins in childhood and is characterized by a short attention span (inattention), an inability to be calm and stay still (hyperactivity), and poor impulse control (impulsivity). Some people with ADHD have problems with only inattention or with hyperactivity and impulsivity, but most have problems related to all three features.\n\nIn people with ADHD, the characteristic behaviors are frequent and severe enough to interfere with the activities of daily living such as school, work, and relationships with others. Because of an inability to stay focused on tasks, people with inattention may be easily distracted, forgetful, avoid tasks that require sustained attention, have difficulty organizing tasks, or frequently lose items.\n\nHyperactivity is usually shown by frequent movement. Individuals with this feature often fidget or tap their foot when seated, leave their seat when it is inappropriate to do so (such as in the classroom), or talk a lot and interrupt others.\n\nImpulsivity can result in hasty actions without thought for the consequences. Individuals with poor impulse control may have difficulty waiting for their turn, deferring to others, or considering their actions before acting.\n\nMore than two-thirds of all individuals with ADHD have additional conditions, including insomnia, mood or anxiety disorders, learning disorders, or substance use disorders. Affected individuals may also have autism spectrum disorder, which is characterized by impaired communication and social interaction, or Tourette syndrome, which is a disorder characterized by repetitive and involuntary movements or noises called tics.\n\nIn most affected individuals, ADHD continues throughout life, but in about one-third of individuals, signs and symptoms of ADHD go away by adulthood.

Complete lack of development of speech and language abilities.

Repeated, individually recognizable, intermittent movements or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement.

An increase in size of the ventricular system of the brain.

Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.

A type of repetitive behavior in which the affected individual repeatedly waves the hands and/or arms rhythmically.

Any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38.0 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in people beyond the typical arrange of 3 months-6 years with no prior history of afebrile seizure.

Highly restricted, fixated interests that are abnormal in intensity or focus (e.g., strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interests).

Moving another person's hand, body part, or body to communicate a desire, e.g. pushing or pulling someone toward a desired object or placing someone's hand on something.

Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium.

Increased susceptibility to otitis media, as manifested by recurrent episodes of otitis media.

An abnormally increased height of the forehead.

Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).

Increased breadth of the nasal bridge (and with it, the nasal root).

Increased distance between the attachments of the alae nasi to the face.

Columella extending inferior to the level of the nasal base, when viewed from the side.

Decreased density/number and/or decreased diameter of lateral eyebrow hairs.