Gotra is very important in Sanatan Dharma. The literal meaning of 'gotra' is very broad. Scholars have also interpreted it appropriately from time to time. 'Go' means senses, while 'tra' means 'to protect', hence gotra also means 'protector from sense shock', which clearly indicates 'sage'.
Generally 'gotra' is considered to be related to the sage tradition. For the Brahmins, 'gotra' is particularly important because Brahmins are considered to be the children of sages. Hence each Brahmin is related to a Rishikul.
In ancient times, gotra tradition started in the name of four sages. These are the sages - Angira, Kashyapa, Vasishta and Bhragu. After some time Jamadagni, Atri, Vishwamitra and Agastya also joined it. In practice, 'gotra' means identity. Which is for Brahmins from their Rishikul.
Later, when the varna system took the form of caste-system, then this identity became related to place and karma. This is the reason why the gotras of the classes other than Brahmins belong mostly to their place of origin or karmakshetra. The main motive behind 'gotra' is that of aggregation, but due to lack of mutual love and harmony in the present times, the importance of gotra has also gradually reduced to only ritualistic formality.
When the gotra is not known:
In Brahmins, when no one has knowledge of his 'gotra', then he chants 'Kashyapa' gotra. This would have been because the sage Kashyapa had more than one marriage and had many sons. Due to having many sons, such Brahmins who do not know their 'gotra' are considered to be related to the sage Rishikul of 'Kashyapa'.
There is no marriage in the same gotra, know what is the story behind it:
Marriage is not allowed in the same gotra in Sanatan Dharma. Inter-caste marriage is opposed in Sanatan Dharma. It has been seen many times that many kinds of incidents have also come to light due to protests. Many people say that one should not marry in a gotra. But the question must be arising in the minds of many people what is a gotra. Gotra means clan or clan, which connects us to our generation. There is a family relationship between people of the same gotra. Mishra gotra for example. This means that the people of the Mishra gotra belong to the same family i.e. the same gotra or clan.
Due to the same gotra in Sanatan Dharma, boys and girls become siblings. Talking of marriage is also considered a sin due to the reason of having siblings. That is why it is said that leaving three gotras and marrying, first gotra own, second mother and then grandmother and then female grandmother.
In Sanatan Dharma, one is not allowed to marry in the same gotra. Due to being of the same gotra, the sutras are the same. Due to having the same quality formula, getting married can cause many problems. Many types of diseases and many types of diseases are found in children born from such marriages. Therefore, it is said not to marry in the same gotra.
It is said that the farther the boy and the girl are, the more superior the marriage is. Children born from such marriages are considered very talented. Such children are very strong. If someone has genetic disease, one should never marry same jeans. Never marry in your close relatives.