Any person residing in the state of Missouri who is in need of genetic services and, as a person, can probably benefit from such services and who is otherwise financially unable to pay for such services shall be entitled to health services without charge to the limit of the appropriations provided for genetic services. Any patient who, or whose parents, guardian or other person legally chargeable with the support of the patient, is able to pay a portion but not all of the expenses for the required services for the patient shall be entitled to the services if the patient or parent, guardian or other person legally charged with the support of the patient shall pay such portion of the expenses to the provider as the patient or parent, guardian or other person legally charged with the support of the patient is reasonably able to pay. However, when the patient is eligible, payments will be made for such services through Medicaid or other insurance benefits available to the patient to the fullest possible extent. The benefits available under the provisions of sections 191.300 to 191.331, 191.340, and 191.365 to 191.380 shall not replace those provided under other federal or state law or under other contractual or legal entitlements of the persons receiving them. This section does not apply to metabolic screenings.