- Hypogonadotropic hypogonadism (HP:0000044): Hypogonadotropic hypogonadism is characterized by reduced function of the gonads (testes in males or ovaries in females) and results from the absence of the gonadal stimulating pituitary hormones: follicle stimulating hormone (FSH) and luteinizing hormone (LH). Evidence: IEA. (OMIM:308750)
- Micropenis (HP:0000054): Abnormally small penis. At birth, the normal penis is about 3 cm (stretched length from pubic tubercle to tip of penis) with micropenis less than 2.0-2.5 cm. Evidence: IEA. (OMIM:308750)
- Olfactory lobe agenesis (HP:0001341). Evidence: IEA. (OMIM:308750)
- Gynecomastia (HP:0000771): Abnormal development of large mammary glands in males resulting in breast enlargement. Evidence: IEA. (OMIM:308750)
- 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:308750)
- Unilateral renal agenesis (HP:0000122): A unilateral form of agenesis of the kidney. Evidence: IEA. (OMIM:308750)
- Decreased circulating luteinizing hormone level (HP:0030344): A reduction in the circulating level of luteinizing hormone (LH). Evidence: PCS. (PMID:6604133)
- Eunuchoid habitus (HP:0003782): A body habitus that is tall, slim and underweight, with long legs and long arms (i.e., arm span exceeds height by 5 cm or more). Evidence: IEA. (OMIM:308750)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: IEA. (OMIM:308750)
- Gonadotropin-releasing hormone deficiency (HP:0003164): Gonadotropin-releasing hormone (GnRH) deficiency (IGD) is characterized by inappropriately low serum concentrations of the gonadotropins LH (luteinizing hormone) and FSH (follicle-stimulating hormone) in the presence of low circulating concentrations of sex steroids (primarily testosterone or estradiol). GnRH is not typically assayed directly because it is released in pulses from the hypothalamus, and its concentration can fluctuate rapidly and in a complex pattern that makes single blood measurements less informative than the pituitary's response. Evidence: IEA. (OMIM:308750)
- Decreased circulating follicle stimulating hormone concentration (HP:0030341): A reduction of the circulating level of follicle-stimulating hormone (FSH). Evidence: PCS. (PMID:6604133)
- Leydig cell insensitivity to gonadotropin (HP:0002929). Evidence: IEA. (OMIM:308750)
- Anosmia (HP:0000458): An inability to perceive odors. This is a general term describing inability to smell arising in any part of the process of smelling from absorption of odorants into the nasal mucous overlying the olfactory epithelium, diffusion to the cilia, binding to olfactory receptor sites, generation of action potentials in olfactory neurons, and perception of a smell. Evidence: IEA. (OMIM:308750)
- Testicular atrophy (HP:0000029): Wasting (atrophy) of the testicle (the male gonad) manifested by a decrease in size and potentially by a loss of fertility. Evidence: IEA. (OMIM:308750)
- 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: IEA. (OMIM:308750)
- X-linked inheritance (HP:0001417): A mode of inheritance that is observed for traits related to a gene encoded on the X chromosome. Evidence: IEA. (OMIM:308750)
- Bimanual synkinesia (HP:0001335): Involuntary movements of one hand that accompany and mirror intentional movements of the opposite hand. Evidence: IEA. (OMIM:308750)
- Spastic paraplegia (HP:0001258): Complete loss of the ability to move the lower limbs accompanied by spasticity of the lower limbs. Evidence: IEA. (OMIM:308750)
- Cryptorchidism (HP:0000028): Testis in inguinal canal. That is, absence of one or both testes from the scrotum owing to failure of the testis or testes to descend through the inguinal canal to the scrotum. Evidence: IEA. (OMIM:308750)
- Sparse pubic hair (HP:0002225): Reduced number or density of pubic hair. Evidence: IEA. (OMIM:308750)
These phenotypes are associated with the disease Kallmann syndrome with spastic paraplegia (OMIM:308750).