Absence of any measurable level of sperm,whereby spermatozoa cannot be observed even after centrifugation of the semen pellet.

Webbing or fusion of the fingers or toes, involving soft parts only or including bone structure. Bony fusions are referred to as "bony" syndactyly if the fusion occurs in a radio-ulnar axis. Fusions of bones of the fingers or toes in a proximo-distal axis are referred to as "symphalangism".

Syndactyly with fusion of toes two to four.

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.

Head circumference below 2 standard deviations below the mean for age and gender.

Familial male hypogonadism is a highly heterogeneous category from which some disorders such as Reifenstein syndrome (312300), Kallmann syndrome (see 308700), isolated gonadotropin deficiency, and some other entities can be separated. The presence of an autosomal recessive form is suggested by the occurrence of parental consanguinity (Nowakowski and Lenz, 1961).