In general, gotra denotes all persons who trace descent in an unbroken male line from a common male ancestor. Panini defines gotra for grammatical purposes as ' apatyam pautraprabhrti gotram' (IV. 1. 162), which means 'the word gotra denotes the progeny (of a sage) beginning with the son's son. When a person says ' I am Kashypasa-gotra' he means that he traces his descent from the ancient sage Kashyapa by unbroken male descent. According to the Baudh‚yanas'rauta-sŻtra Vishv‚mitra, Jamadagni, Bharadv‚ja, Gautama, Atri, Vasishtha, Kashyapa and Agastya are 8 sages; the progeny of these eight sages is declared to be gotras. This enumeration of eight primary gotras seems to have been known to P‚Nini. The offspring (apatya) of these eight are gotras and others than these are called ' gotr‚vayava '.
There are 49 established Hindu gotras. All members of a particular gotra are believed to possess certain common characteristics by way of nature or profession. Many theories have been propounded to explain this system. According to the brahminical theory, the Brahmins are the direct descendants of seven or eight sages who are believed to be the mind-born sons of Brahma. They are Gautama, Bharadvaja, Vishvamitra, Jamadagni, Vasishtha, Kashyapa and Atri. To this list, Agastya is also sometimes added. These eight sages are called gotrakarins from whom all the 49 gotras (especially of the Brahmins) have evolved. For instance, from Atri sprang the Atreya and Gavisthiras gotras.
A gotra must be distinguished from a kula. A kula is a set of people following similar cultural rituals, often worshiping the same divinity (the Kula-Devata, god of the clan). Kula does not relate to lineage or caste. In fact, it is possible to change one's kula, based on one's faith or Iṣṭa-devatā.
It is common practice in preparation for Hindu marriage to inquire about the kula-gotra (meaning clan lineage) of the bride and groom before approving the marriage. In almost all Hindu families, marriagewithin the same gotra is prohibited, since people with same gotra are considered to be siblings. But marriage within the kula is allowed and even preferred.
Shudras also have gotras, and follow them in marriages. For example a weaver falls under Markandeya gotra. Markandeya was known be a Maharishi and had 60 sons. Marriages are held within Markandeya but never in same family name. So, every weaver falls under one of these gotra. The family name is given by the Brahmin or Guru's name.
In a court case "Madhavrao vs Raghavendrarao" which involved a Deshastha Brahmin couple, the German scholar Max Mueller's definition of gotra as descending from eight sages and then branching out to several families was thrown out by reputed judges of a Bombay High Court. The court called the idea of Brahmin families descending from an unbroken line of common ancestors as indicated by the names of their respective gotras impossible to accept. The court consulted relevant Hindu texts and stressed the need for Hindu society and law to keep up with the times emphasizing that notions of good social behavior and the general ideology of the Hindu society had changed. The court also said that the mass of material in the Hindu texts is so vast and full of contradictions that it is almost an impossible task to reduce it to order and coherence.
Origin of gotra
Gotra is the Sanskrit term for a much older system of tribal clans. The Sanskrit term "Gotra" was initially used by the Vedicpeople for the identification of the lineages. Generally, these lineages mean patrilineal descent from the sages or rishis in Brahmins, warriors and administrators in Kshatriyas and ancestral trademen in Vaisyas.
The lineage system, either patrilineal or matrilineal, was followed by the South Asian people. In present-day Hinduism, Gotra is applied to all the lineage systems.
The case of sage Vishwamitra is the example. Thus the gotra must have been of the lineage of the learning one chose rather than the lineage of one's birth. Rama is stated to be the descendant of Ikshwaku, but the lineage was broken when Kalmashpada got his son through Niyoga of Vasishta with Kalmashapad's wife Madayanthi, and not through a biological liaison. Yet Rama is said to be Ikshwaku's descendant and not of Vasishta. Some claim of a continuous biological linkage with the moola purusha [or most significant personality] of the Gothra, where as it need not be the case. Some times, a Gotra is based on the Guru for the family or one of the ancestors.
Marriages within a gotra reflect inbreeding with significant health consequences. Inbreeding generally increases pre-reproductive mortality and crude mortality increases with inbreeding in proportion to the mortality rate.
Marriages and gotras
In a patrilineal Hindu society (most common), the bride belongs to her father's gotra before the marriage, and to her husband's gotra after the marriage. The groom on the other hand only belongs to his father's gotra throughout his life.
Marriages within the gotra ('sagotra' marriages) are not permitted under the rule of exogamy in the traditional matrimonial system. The word 'sagotra' is union the words 'sa' + gotra, where 'sa' means same or similar. People within the gotra are regarded as kin and marrying such a person would be thought of as incest. The Tamil words 'sagotharan' (brother) and 'sagothari' (sister) derive their roots from the Sanskrit word 'sahodara' (सहोदर) meaning co-uterine or born of the same womb. In communities where gotra membership passed from father to children, marriages were allowed between maternal uncle and niece, while such marriages were forbidden in matrilineal communities, like Malayalisand Tuluvas, where gotra membership was passed down from the mother.
A much more common characteristic of south Indian Hindu society is permission for marriage between cross-cousins (children of brother and sister). Thus, a man is allowed to marry his maternal uncle's daughter or his paternal aunt's daughter, but is not allowed to marry his father's brother's daughter. She would be considered a parallel cousin who is treated as a sister.
North Indian Hindu society not only follows the rules of gotra for marriages, but also had many regulations which went beyond the basic definition of gotra and had a broader definition of incestuousness. Some communities in North India do not allow marriage with some other communities on the lines that both the Communities are having brotherhood.
An acceptable social workaround for sagotra marriages is to perform a 'Dathu' (adoption) of the bride to a family of different gotra (usually dathu is given to the bride's maternal uncle who obviously belongs to different gotra by the same rule) and let them perform the 'kanniyadhanam' ('kanniya' (girl) + 'dhanam' (to donate)). However, this is easier said as it would be quite difficult for the bride's father to watch another man give his daughter's hand away in marriage in his own presence.
Khap panchayats in Haryana have been making a huge fuss over banning "same gotra marriages." Kadyan Khap International convener Naresh Kadyan had moved a petition seeking amendment to the Hindu Marriage Act (HMA) so as to legally prohibit marriages in the same gotra. However, the petition was dismissed as withdrawn after a vacation Bench of Justices S N Dhingra and A K Pathak of the Delhi High Court warned that a heavy cost would be imposed on the petitioner for wasting the time of the court. In course of the proceedings, the bench observed, “You don’t know what is a gotra. Which Hindu text prescribes banning of sagotra (same clan) marriage? Why are you wasting the time of the court? If you are not able to substantiate your words, then you should not have come before the court.”