Early Puberty Causes and Genetics

Early Puberty Causes and Genetics

Adolescence (puberty) is the transition period from childhood to adulthood, when the individual's secondary sex characteristics (genital and armpit hair growth, growth spurt, breast development, growth of the hips, testis (ovary) and scrotum, voice change, acne formation) and physical fertility develop.


In Girls

The first sign of puberty is breast enlargement, which may initially be unilateral. Pubic and armpit hair and axillary odor usually begin after breast enlargement. Menarche usually occurs 2-3 years after the onset of breast growth. Pubertal growth spurt is evident in early adolescence and usually during the initial assessment.

In Men

The first sign of puberty is testicular enlargement. Enlargement of the penis and scrotum usually occurs one year after testicular enlargement. Pubertal growth spurt occurs later in puberty in boys.

Precocious puberty (precocious puberty);

It is the enlargement of the breast development before the age of 8 in girls and the volume of the testis before the age of 9 in boys.

Risk factors:

  • Female gender
  • Race (African-American)
  • Exposure to sex hormones
  • Obesity

Precocious puberty is divided into three as central, peripheral and normal variant. Puberty begins with the functioning of the hypothalamus-pituitary and gonad (ovary) pathways. Central precocious puberty occurs as a result of early activation of the hypothalamic-pituitary-gonadal pathway. In the early period, the increase in gonadal hormones that occur without the activation of the hypothalamus-pituitary-gonadal pathway is called peripheral puberty precox. Central precocious puberty constitutes the majority of precocious puberty cases.

Causes of central puberty precox:

  • Idiopathic (Familial/non-familial)
  • Genetics: McCune Albright Syndrome, various gene mutations
  • SSS tumors
  • SSS damage

Peripheral precocious puberty causes:

  • Gonadal
  • Tumors

Genetic problems: McCune Albright Syndrome, various gene mutations

  • Adrenal
  • Tumors
  • Genetic problems: Congenital Adrenal Hyperplasia, various gene mutations
  • Other (hormone disorders, drug use)


Puberty is a complex process controlled by genetic and non-genetic factors. Because;

  • In cases of unknown cause
  • In familial cases

genetic studies are important.

Genetic tests for prepubertal precox at our center:

  • Congenital adrenal hyperplasia
  • McCune-Albright syndrome
  • Exome analysis

In patients who have a genetic disease but have not been diagnosed, additional findings that may accompany the disease cannot be predicted and the patient cannot be treated. In untreated cases:

  • Short stature
  • Psychosocial problems (negative psychological consequences-behavioral problems, poor self-esteem, high anxiety, irritability)
  • Additional disease-specific problems